From e1a334b57249353b8e8bab707080369e0f3820c3 Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Fri, 15 Nov 2024 15:46:11 +0000
Subject: [PATCH 1/6] Process graphviz diagrams.

Replaces mermaid support (which doesn't work well with reveal.js and RevealMarkdown).
---
 Cargo.lock | 575 +++++++++++++++++++++++++++++++++++++++--------------
 Cargo.toml |   1 +
 src/lib.rs |  38 ++++
 3 files changed, 470 insertions(+), 144 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index cc3576b..1f1d2db 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4,78 +4,94 @@ version = 3
 
 [[package]]
 name = "aho-corasick"
-version = "1.1.2"
+version = "1.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
 dependencies = [
  "memchr",
 ]
 
 [[package]]
 name = "anstream"
-version = "0.6.4"
+version = "0.6.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2ab91ebe16eb252986481c5b62f6098f3b698a45e34b5b98200cf20dd2484a44"
+checksum = "8acc5369981196006228e28809f761875c0327210a891e941f4c683b3a99529b"
 dependencies = [
  "anstyle",
  "anstyle-parse",
  "anstyle-query",
  "anstyle-wincon",
  "colorchoice",
+ "is_terminal_polyfill",
  "utf8parse",
 ]
 
 [[package]]
 name = "anstyle"
-version = "1.0.4"
+version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7079075b41f533b8c61d2a4d073c4676e1f8b249ff94a393b0595db304e0dd87"
+checksum = "55cc3b69f167a1ef2e161439aa98aed94e6028e5f9a59be9a6ffb47aef1651f9"
 
 [[package]]
 name = "anstyle-parse"
-version = "0.2.2"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "317b9a89c1868f5ea6ff1d9539a69f45dffc21ce321ac1fd1160dfa48c8e2140"
+checksum = "3b2d16507662817a6a20a9ea92df6652ee4f94f914589377d69f3b21bc5798a9"
 dependencies = [
  "utf8parse",
 ]
 
 [[package]]
 name = "anstyle-query"
-version = "1.0.0"
+version = "1.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ca11d4be1bab0c8bc8734a9aa7bf4ee8316d462a08c6ac5052f888fef5b494b"
+checksum = "79947af37f4177cfead1110013d678905c37501914fba0efea834c3fe9a8d60c"
 dependencies = [
- "windows-sys",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
 name = "anstyle-wincon"
-version = "3.0.1"
+version = "3.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0699d10d2f4d628a98ee7b57b289abbc98ff3bad977cb3152709d4bf2330628"
+checksum = "2109dbce0e72be3ec00bed26e6a7479ca384ad226efdd66db8fa2e3a38c83125"
 dependencies = [
  "anstyle",
- "windows-sys",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
 name = "bitflags"
-version = "1.3.2"
+version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
 
 [[package]]
-name = "bitflags"
-version = "2.4.1"
+name = "block-buffer"
+version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "327762f6e5a765692301e5bb513e0d9fef63be86bbc14528052b1cd3e6f03e07"
+checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
+dependencies = [
+ "generic-array",
+]
+
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "clap"
-version = "4.4.7"
+version = "4.5.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac495e00dcec98c83465d5ad66c5c4fabd652fd6686e7c6269b117e729a6f17b"
+checksum = "fb3b4b9e5a7c7514dfa52869339ee98b3156b0bfb4e8a77c4ff4babb64b1604f"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -83,9 +99,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.4.7"
+version = "4.5.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c77ed9a32a62e6ca27175d00d29d05ca32e396ea1eb5fb01d8256b669cec7663"
+checksum = "b17a95aa67cc7b5ebd32aa5370189aa0d79069ef1c64ce893bd30fb24bff20ec"
 dependencies = [
  "anstream",
  "anstyle",
@@ -95,33 +111,77 @@ dependencies = [
 
 [[package]]
 name = "clap_derive"
-version = "4.4.7"
+version = "4.5.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf9804afaaf59a91e75b022a30fb7229a7901f60c755489cc61c9b423b836442"
+checksum = "4ac6a0c7b1a9e9a5186361f67dfa1b88213572f427fb9ab038efb2bd8c582dab"
 dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.87",
 ]
 
 [[package]]
 name = "clap_lex"
-version = "0.6.0"
+version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "702fc72eb24e5a1e48ce58027a675bc24edd52096d5397d4aea7c6dd9eca0bd1"
+checksum = "afb84c814227b90d6895e01398aee0d8033c00e7466aca416fb6a8e0eb19d8a7"
 
 [[package]]
 name = "colorchoice"
-version = "1.0.0"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b63caa9aa9397e2d9480a9b13673856c78d8ac123288526c37d7839f2a86990"
+
+[[package]]
+name = "cpufeatures"
+version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
+checksum = "0ca741a962e1b0bff6d724a1a0958b686406e853bb14061f218562e1896f95e6"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "crypto-common"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
+[[package]]
+name = "digest"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+]
+
+[[package]]
+name = "dot-generator"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0aaac7ada45f71873ebce336491d1c1bc4a7c8042c7cea978168ad59e805b871"
+dependencies = [
+ "dot-structures",
+]
+
+[[package]]
+name = "dot-structures"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "675e35c02a51bb4d4618cb4885b3839ce6d1787c97b664474d9208d074742e20"
 
 [[package]]
 name = "env_logger"
-version = "0.10.0"
+version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "85cdab6a89accf66733ad5a1693a4dcced6aeff64602b634530dd73c1f3ee9f0"
+checksum = "4cd405aab171cb85d6735e5c8d9db038c17d3ca007a4d2c25f337935c3d90580"
 dependencies = [
  "humantime",
  "is-terminal",
@@ -138,12 +198,28 @@ checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
 
 [[package]]
 name = "errno"
-version = "0.3.5"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac3e13f66a2f95e32a39eaa81f6b95d42878ca0e1db0c7543723dfe12557e860"
+checksum = "534c5cf6194dfab3db3242765c03bbe257cf92f22b38f6bc0c58d59108a820ba"
 dependencies = [
  "libc",
- "windows-sys",
+ "windows-sys 0.52.0",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "486f806e73c5707928240ddc295403b1b93c96a02038563881c4a2fd84b81ac4"
+
+[[package]]
+name = "generic-array"
+version = "0.14.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85649ca51fd72272d7821adaf274ad91c288277713d9c18820d8499a7ff69e9a"
+dependencies = [
+ "typenum",
+ "version_check",
 ]
 
 [[package]]
@@ -155,23 +231,50 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c4567c8db10ae91089c99af84c68c38da3ec2f087c3f82960bcdbf3656b6f4d7"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
+[[package]]
+name = "graphviz-rust"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f7892a4538fc9aa3658ae6962774428487c16e11663c58c594357975377c901"
+dependencies = [
+ "dot-generator",
+ "dot-structures",
+ "into-attr",
+ "into-attr-derive",
+ "pest",
+ "pest_derive",
+ "rand",
+ "tempfile",
+]
+
 [[package]]
 name = "hashbrown"
-version = "0.14.2"
+version = "0.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f93e7192158dbcda357bdec5fb5788eebf8bbac027f3f33e719d29135ae84156"
+checksum = "3a9bfc1af68b1726ea47d3d5109de126281def866b33970e10fbab11b5dafab3"
 
 [[package]]
 name = "heck"
-version = "0.4.1"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
+checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
 [[package]]
 name = "hermit-abi"
-version = "0.3.3"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d77f7ec81a6d05a3abb01ab6eb7590f6083d08449fe5a1c8b1e620283546ccb7"
+checksum = "fbf6a919d6cf397374f7dfeeea91d974c7c0a7221d0d0f4f20d859d329e53fcc"
 
 [[package]]
 name = "humantime"
@@ -181,42 +284,70 @@ checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
 [[package]]
 name = "indexmap"
-version = "2.0.2"
+version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8adf3ddd720272c6ea8bf59463c04e0f93d0bbf7c5439b691bca2987e0270897"
+checksum = "707907fe3c25f5424cce2cb7e1cbcafee6bdbe735ca90ef77c29e84591e5b9da"
 dependencies = [
  "equivalent",
  "hashbrown",
 ]
 
+[[package]]
+name = "into-attr"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18b48c537e49a709e678caec3753a7dba6854661a1eaa27675024283b3f8b376"
+dependencies = [
+ "dot-structures",
+]
+
+[[package]]
+name = "into-attr-derive"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ecac7c1ae6cd2c6a3a64d1061a8bdc7f52ff62c26a831a2301e54c1b5d70d5b1"
+dependencies = [
+ "dot-generator",
+ "dot-structures",
+ "into-attr",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "is-terminal"
-version = "0.4.9"
+version = "0.4.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb0889898416213fab133e1d33a0e5858a48177452750691bde3666d0fdbaf8b"
+checksum = "261f68e344040fbd0edea105bef17c66edf46f984ddb1115b775ce31be948f4b"
 dependencies = [
  "hermit-abi",
- "rustix",
- "windows-sys",
+ "libc",
+ "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "is_terminal_polyfill"
+version = "1.70.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7943c866cc5cd64cbc25b2e01621d07fa8eb2a1a23160ee81ce38704e97b8ecf"
+
 [[package]]
 name = "libc"
-version = "0.2.149"
+version = "0.2.162"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a08173bc88b7955d1b3145aa561539096c421ac8debde8cbc3612ec635fee29b"
+checksum = "18d287de67fe55fd7e1581fe933d965a5a9477b38e949cfa9f8574ef01506398"
 
 [[package]]
 name = "linux-raw-sys"
-version = "0.4.10"
+version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da2479e8c062e40bf0066ffa0bc823de0a9368974af99c9f6df941d2c231e03f"
+checksum = "78b3ae25bc7c8c38cec158d1f2757ee79e9b3740fbc7ccf0e59e4b08d793fa89"
 
 [[package]]
 name = "log"
-version = "0.4.20"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"
+checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
 
 [[package]]
 name = "mdslides"
@@ -224,6 +355,7 @@ version = "0.4.0"
 dependencies = [
  "clap",
  "env_logger",
+ "graphviz-rust",
  "log",
  "pulldown-cmark",
  "serde",
@@ -233,26 +365,86 @@ dependencies = [
 
 [[package]]
 name = "memchr"
-version = "2.6.4"
+version = "2.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
+
+[[package]]
+name = "once_cell"
+version = "1.20.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1261fe7e33c73b354eab43b1273a57c8f967d0391e80353e51f764ac02cf6775"
+
+[[package]]
+name = "pest"
+version = "2.7.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "879952a81a83930934cbf1786752d6dedc3b1f29e8f8fb2ad1d0a36f377cf442"
+dependencies = [
+ "memchr",
+ "thiserror",
+ "ucd-trie",
+]
+
+[[package]]
+name = "pest_derive"
+version = "2.7.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d214365f632b123a47fd913301e14c946c61d1c183ee245fa76eb752e59a02dd"
+dependencies = [
+ "pest",
+ "pest_generator",
+]
+
+[[package]]
+name = "pest_generator"
+version = "2.7.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f665ee40bc4a3c5590afb1e9677db74a508659dfd71e126420da8274909a0167"
+checksum = "eb55586734301717aea2ac313f50b2eb8f60d2fc3dc01d190eefa2e625f60c4e"
+dependencies = [
+ "pest",
+ "pest_meta",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.87",
+]
+
+[[package]]
+name = "pest_meta"
+version = "2.7.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b75da2a70cf4d9cb76833c990ac9cd3923c9a8905a8929789ce347c84564d03d"
+dependencies = [
+ "once_cell",
+ "pest",
+ "sha2",
+]
+
+[[package]]
+name = "ppv-lite86"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77957b295656769bb8ad2b6a6b09d897d94f05c41b069aede1fcdaa675eaea04"
+dependencies = [
+ "zerocopy",
+]
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.69"
+version = "1.0.89"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "134c189feb4956b20f6f547d2cf727d4c0fe06722b20a0eec87ed445a97f92da"
+checksum = "f139b0662de085916d1fb67d2b4169d1addddda1919e696f3252b740b629986e"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "pulldown-cmark"
-version = "0.9.3"
+version = "0.9.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77a1a2f1f0a7ecff9c31abbe177637be0e97a0aef46cf8738ece09327985d998"
+checksum = "57206b407293d2bcd3af849ce869d52068623f19e1b5ff8e8778e3309439682b"
 dependencies = [
- "bitflags 1.3.2",
+ "bitflags",
  "getopts",
  "memchr",
  "unicase",
@@ -260,18 +452,48 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.33"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5267fca4496028628a95160fc423a33e8b2e6af8a5302579e322e4b520293cae"
+checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
 dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
+]
+
 [[package]]
 name = "regex"
-version = "1.10.2"
+version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "380b951a9c5e80ddfd6136919eef32310721aa4aacd4889a8d39124b026ab343"
+checksum = "b544ef1b4eac5dc2db33ea63606ae9ffcfac26c1416a2806ae0bf5f56b201191"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -281,9 +503,9 @@ dependencies = [
 
 [[package]]
 name = "regex-automata"
-version = "0.4.3"
+version = "0.4.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5f804c7828047e88b2d32e2d7fe5a105da8ee3264f01902f796c8e067dc2483f"
+checksum = "809e8dc61f6de73b46c85f4c96486310fe304c434cfa43669d7b40f711150908"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -292,96 +514,131 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.8.2"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
+checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 
 [[package]]
 name = "rustix"
-version = "0.38.21"
+version = "0.38.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b426b0506e5d50a7d8dafcf2e81471400deb602392c7dd110815afb4eaf02a3"
+checksum = "99e4ea3e1cdc4b559b8e5650f9c8e5998e3e5c1343b4eaf034565f32318d63c0"
 dependencies = [
- "bitflags 2.4.1",
+ "bitflags",
  "errno",
  "libc",
  "linux-raw-sys",
- "windows-sys",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
 name = "serde"
-version = "1.0.190"
+version = "1.0.215"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "91d3c334ca1ee894a2c6f6ad698fe8c435b76d504b13d436f0685d648d6d96f7"
+checksum = "6513c1ad0b11a9376da888e3e0baa0077f1aed55c17f50e7b2397136129fb88f"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.190"
+version = "1.0.215"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67c5609f394e5c2bd7fc51efda478004ea80ef42fee983d5c67a65e34f32c0e3"
+checksum = "ad1e866f866923f252f05c889987993144fb74e722403468a4ebd70c3cd756c0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.87",
 ]
 
 [[package]]
 name = "serde_spanned"
-version = "0.6.4"
+version = "0.6.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12022b835073e5b11e90a14f86838ceb1c8fb0325b72416845c487ac0fa95e80"
+checksum = "87607cb1398ed59d48732e575a4c28a7a8ebf2454b964fe3f224f2afc07909e1"
 dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "sha2"
+version = "0.10.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "793db75ad2bcafc3ffa7c68b215fee268f537982cd901d132f89c6343f3a3dc8"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "strsim"
-version = "0.10.0"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
+
+[[package]]
+name = "syn"
+version = "1.0.109"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
+checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
 
 [[package]]
 name = "syn"
-version = "2.0.38"
+version = "2.0.87"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e96b79aaa137db8f61e26363a0c9b47d8b4ec75da28b7d1d614c2303e232408b"
+checksum = "25aa4ce346d03a6dcd68dd8b4010bcb74e54e62c90c573f394c46eae99aba32d"
 dependencies = [
  "proc-macro2",
  "quote",
  "unicode-ident",
 ]
 
+[[package]]
+name = "tempfile"
+version = "3.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28cce251fcbc87fac86a866eeb0d6c2d536fc16d06f184bb61aeae11aa4cee0c"
+dependencies = [
+ "cfg-if",
+ "fastrand",
+ "once_cell",
+ "rustix",
+ "windows-sys 0.59.0",
+]
+
 [[package]]
 name = "termcolor"
-version = "1.3.0"
+version = "1.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6093bad37da69aab9d123a8091e4be0aa4a03e4d601ec641c327398315f62b64"
+checksum = "06794f8f6c5c898b3275aebefa6b8a1cb24cd2c6c79397ab15774837a0bc5755"
 dependencies = [
  "winapi-util",
 ]
 
 [[package]]
 name = "thiserror"
-version = "1.0.50"
+version = "1.0.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f9a7210f5c9a7156bb50aa36aed4c95afb51df0df00713949448cf9e97d382d2"
+checksum = "b6aaf5339b578ea85b50e080feb250a3e8ae8cfcdff9a461c9ec2904bc923f52"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.50"
+version = "1.0.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "266b2e40bc00e5a6c09c3584011e08b06f123c00362c92b975ba9843aaaa14b8"
+checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.87",
 ]
 
 [[package]]
@@ -398,9 +655,9 @@ dependencies = [
 
 [[package]]
 name = "toml_datetime"
-version = "0.6.5"
+version = "0.6.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3550f4e9685620ac18a50ed434eb3aec30db8ba93b0287467bca5826ea25baf1"
+checksum = "0dd7358ecb8fc2f8d014bf86f6f638ce72ba252a2c3a2572f2a795f1d23efb41"
 dependencies = [
  "serde",
 ]
@@ -418,88 +675,91 @@ dependencies = [
  "winnow",
 ]
 
+[[package]]
+name = "typenum"
+version = "1.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "42ff0bf0c66b8238c6f3b578df37d0b7848e55df8577b3f74f92a69acceeb825"
+
+[[package]]
+name = "ucd-trie"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2896d95c02a80c6d6a5d6e953d479f5ddf2dfdb6a244441010e373ac0fb88971"
+
 [[package]]
 name = "unicase"
-version = "2.7.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7d2d4dafb69621809a81864c9c1b864479e1235c0dd4e199924b9742439ed89"
-dependencies = [
- "version_check",
-]
+checksum = "7e51b68083f157f853b6379db119d1c1be0e6e4dec98101079dec41f6f5cf6df"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.12"
+version = "1.0.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
+checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
 
 [[package]]
 name = "unicode-width"
-version = "0.1.11"
+version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e51733f11c9c4f72aa0c160008246859e340b00807569a0da0e7a1079b27ba85"
+checksum = "7dd6e30e90baa6f72411720665d41d89b9a3d039dc45b8faea1ddd07f617f6af"
 
 [[package]]
 name = "utf8parse"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
+checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
 
 [[package]]
 name = "version_check"
-version = "0.9.4"
+version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
+checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
 [[package]]
-name = "winapi"
-version = "0.3.9"
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
-dependencies = [
- "winapi-i686-pc-windows-gnu",
- "winapi-x86_64-pc-windows-gnu",
-]
-
-[[package]]
-name = "winapi-i686-pc-windows-gnu"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
 [[package]]
 name = "winapi-util"
-version = "0.1.6"
+version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f29e6f9198ba0d26b4c9f07dbe6f9ed633e1f3d5b8b414090084349e46a52596"
+checksum = "cf221c93e13a30d793f7645a0e7762c55d169dbb0a49671918a2319d289b10bb"
 dependencies = [
- "winapi",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
-name = "winapi-x86_64-pc-windows-gnu"
-version = "0.4.0"
+name = "windows-sys"
+version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
+dependencies = [
+ "windows-targets",
+]
 
 [[package]]
 name = "windows-sys"
-version = "0.48.0"
+version = "0.59.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "677d2418bec65e3338edb076e806bc1ec15693c5d0104683f2efe857f61056a9"
+checksum = "1e38bc4d79ed67fd075bcc251a1c39b32a1776bbe92e5bef1f0bf1f8c531853b"
 dependencies = [
  "windows-targets",
 ]
 
 [[package]]
 name = "windows-targets"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a2fa6e2155d7247be68c096456083145c183cbbbc2764150dda45a87197940c"
+checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
 dependencies = [
  "windows_aarch64_gnullvm",
  "windows_aarch64_msvc",
  "windows_i686_gnu",
+ "windows_i686_gnullvm",
  "windows_i686_msvc",
  "windows_x86_64_gnu",
  "windows_x86_64_gnullvm",
@@ -508,51 +768,78 @@ dependencies = [
 
 [[package]]
 name = "windows_aarch64_gnullvm"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b38e32f0abccf9987a4e3079dfb67dcd799fb61361e53e2882c3cbaf0d905d8"
+checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
 
 [[package]]
 name = "windows_aarch64_msvc"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc35310971f3b2dbbf3f0690a219f40e2d9afcf64f9ab7cc1be722937c26b4bc"
+checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
 
 [[package]]
 name = "windows_i686_gnu"
-version = "0.48.5"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a75915e7def60c94dcef72200b9a8e58e5091744960da64ec734a6c6e9b3743e"
+checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
 
 [[package]]
 name = "windows_i686_msvc"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8f55c233f70c4b27f66c523580f78f1004e8b5a8b659e05a4eb49d4166cca406"
+checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
 
 [[package]]
 name = "windows_x86_64_gnu"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "53d40abd2583d23e4718fddf1ebec84dbff8381c07cae67ff7768bbf19c6718e"
+checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
 
 [[package]]
 name = "windows_x86_64_gnullvm"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b7b52767868a23d5bab768e390dc5f5c55825b6d30b86c844ff2dc7414044cc"
+checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
 
 [[package]]
 name = "windows_x86_64_msvc"
-version = "0.48.5"
+version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
+checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
 [[package]]
 name = "winnow"
-version = "0.5.17"
+version = "0.5.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a3b801d0e0a6726477cc207f60162da452f3a95adb368399bef20a946e06f65c"
+checksum = "f593a95398737aeed53e489c785df13f3618e41dbcd6718c6addbf1395aa6876"
 dependencies = [
  "memchr",
 ]
+
+[[package]]
+name = "zerocopy"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
+dependencies = [
+ "byteorder",
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.87",
+]
diff --git a/Cargo.toml b/Cargo.toml
index b190d99..23c4f05 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,6 +15,7 @@ version = "0.4.0"
 clap = {version = "4", features = ["derive"]}
 env_logger = "0.10"
 log = "0.4"
+graphviz-rust = "0.9.3"
 pulldown-cmark = "0.9.2"
 serde = {version = "1", features = ["derive"]}
 thiserror = "1"
diff --git a/src/lib.rs b/src/lib.rs
index 1d7fb91..46eaac2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -237,8 +237,46 @@ pub fn generate_deck(
 
     let mut output_file = std::fs::File::create(out_path)?;
 
+    let mut collecting_diagram: Option<String> = None;
     let mut first = true;
     for line in generated.lines() {
+        // Find end-of-block, in case it's the end of a diagram.
+        if line == "```" {
+            if let Some(diagram_str) = collecting_diagram.take() {
+                // This is the end of a mermaid block
+                println!("Got graph: {:?}", diagram_str);
+                let diagram = graphviz_rust::exec_dot(
+                    diagram_str,
+                    vec![graphviz_rust::cmd::CommandArg::Format(
+                        graphviz_rust::cmd::Format::Svg,
+                    )],
+                )
+                .expect("Failed to generate graph");
+                // insert the SVG in-line
+                writeln!(output_file, "<figure>")?;
+                output_file.write_all(&diagram)?;
+                writeln!(output_file, "</figure>")?;
+                // Don't emit the code fence
+                continue;
+            }
+        }
+
+        // Are we in a diagram?
+        if let Some(graph_str) = collecting_diagram.as_mut() {
+            graph_str.push_str(line);
+            graph_str.push('\n');
+            // Don't emit the mermaid code
+            continue;
+        }
+
+        // starting a new diagram
+        if line.starts_with("```dot") && line.contains("process") {
+            collecting_diagram = Some(String::new());
+            // Don't emit the code fence
+            continue;
+        }
+
+        // Fixup headings into slide breaks
         if line.starts_with("## ") || line.starts_with("# ") {
             // Don't put a --- before the first heading, as it's our first slide
             if !first {

From a5575679eac073232e7ba38dc291af8a8a94332c Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Fri, 15 Nov 2024 15:55:37 +0000
Subject: [PATCH 2/6] Bump MSRV to 1.74

---
 .github/workflows/check.yml | 6 +++---
 README.md                   | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 26efc9e..6e91a4d 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -22,8 +22,8 @@ jobs:
         run: cargo build
       - name: Clippy
         run: cargo clippy --all-targets --all-features
-      - name: Build with 1.70
+      - name: Build with 1.74
         run: |
           cargo clean
-          rustup update 1.70 --no-self-update
-          cargo +1.70 build
+          rustup update 1.74 --no-self-update
+          cargo +1.74 build
diff --git a/README.md b/README.md
index 8d2809c..a8815b0 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ You can see an example of using this tool at <https://github.com/ferrous-systems
 
 ## MSRV
 
-We check this crate compiles with Rust 1.70.
+We check this crate compiles with Rust 1.74.
 
 ## Changelog
 

From 23daf8c2628404aab568ec0c5a77a5d6a27b68f2 Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Wed, 20 Nov 2024 10:01:24 +0000
Subject: [PATCH 3/6] Fix comments and add some logging.

---
 src/lib.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 46eaac2..434fe31 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -243,8 +243,12 @@ pub fn generate_deck(
         // Find end-of-block, in case it's the end of a diagram.
         if line == "```" {
             if let Some(diagram_str) = collecting_diagram.take() {
-                // This is the end of a mermaid block
-                println!("Got graph: {:?}", diagram_str);
+                // This is the end of a dot block
+                log::debug!("Got graph: {:?}", diagram_str);
+                log::info!(
+                    "Calling graphviz to render diagram in {}",
+                    in_path.display()
+                );
                 let diagram = graphviz_rust::exec_dot(
                     diagram_str,
                     vec![graphviz_rust::cmd::CommandArg::Format(
@@ -265,7 +269,7 @@ pub fn generate_deck(
         if let Some(graph_str) = collecting_diagram.as_mut() {
             graph_str.push_str(line);
             graph_str.push('\n');
-            // Don't emit the mermaid code
+            // Don't emit the dot code
             continue;
         }
 

From b18add3ccac097e494331a8b33b5f942aad451ce Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Thu, 21 Nov 2024 10:49:17 +0000
Subject: [PATCH 4/6] Add some test cases.

---
 .github/workflows/check.yml        |  6 ++-
 Cargo.lock                         | 70 +++++++++++++++++++++++-------
 Cargo.toml                         |  3 ++
 tests/.gitignore                   |  1 +
 tests/data_in/.gitignore           |  1 +
 tests/data_in/book.toml            |  6 +++
 tests/data_in/index_template.html  | 12 +++++
 tests/data_in/src/SUMMARY.md       |  4 ++
 tests/data_in/src/chapter_1.md     |  9 ++++
 tests/data_in/src/chapter_2.md     | 10 +++++
 tests/data_in/template.html        | 13 ++++++
 tests/data_out/.keep               |  0
 tests/reference.rs                 | 44 +++++++++++++++++++
 tests/reference_out/chapter_1.html | 24 ++++++++++
 tests/reference_out/chapter_2.html | 38 ++++++++++++++++
 tests/reference_out/index.html     | 17 ++++++++
 16 files changed, 242 insertions(+), 16 deletions(-)
 create mode 100644 tests/.gitignore
 create mode 100644 tests/data_in/.gitignore
 create mode 100644 tests/data_in/book.toml
 create mode 100644 tests/data_in/index_template.html
 create mode 100644 tests/data_in/src/SUMMARY.md
 create mode 100644 tests/data_in/src/chapter_1.md
 create mode 100644 tests/data_in/src/chapter_2.md
 create mode 100644 tests/data_in/template.html
 create mode 100644 tests/data_out/.keep
 create mode 100644 tests/reference.rs
 create mode 100644 tests/reference_out/chapter_1.html
 create mode 100644 tests/reference_out/chapter_2.html
 create mode 100644 tests/reference_out/index.html

diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 6e91a4d..553d513 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -15,11 +15,15 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
+      - name: Add tools
+        run: sudo apt-get update -y && sudo apt-get install -y graphviz
       - name: Format
         run: cargo fmt --check
       - name: Build
         run: cargo build
+      - name: Test
+        run: cargo test
       - name: Clippy
         run: cargo clippy --all-targets --all-features
       - name: Build with 1.74
diff --git a/Cargo.lock b/Cargo.lock
index 1f1d2db..c96af82 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -118,7 +118,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.87",
+ "syn 2.0.89",
 ]
 
 [[package]]
@@ -212,6 +212,26 @@ version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "486f806e73c5707928240ddc295403b1b93c96a02038563881c4a2fd84b81ac4"
 
+[[package]]
+name = "folder_compare"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7cc8b9547e207c7e5233e593c59919ffdb978f17d1155ea9484cc46cb3e2397"
+dependencies = [
+ "fxhash",
+ "regex",
+ "walkdir",
+]
+
+[[package]]
+name = "fxhash"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c31b6d751ae2c7f11320402d34e41349dd1016f8d5d45e48c4312bc8625af50c"
+dependencies = [
+ "byteorder",
+]
+
 [[package]]
 name = "generic-array"
 version = "0.14.7"
@@ -333,9 +353,9 @@ checksum = "7943c866cc5cd64cbc25b2e01621d07fa8eb2a1a23160ee81ce38704e97b8ecf"
 
 [[package]]
 name = "libc"
-version = "0.2.162"
+version = "0.2.164"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "18d287de67fe55fd7e1581fe933d965a5a9477b38e949cfa9f8574ef01506398"
+checksum = "433bfe06b8c75da9b2e3fbea6e5329ff87748f0b144ef75306e674c3f6f7c13f"
 
 [[package]]
 name = "linux-raw-sys"
@@ -355,6 +375,7 @@ version = "0.4.0"
 dependencies = [
  "clap",
  "env_logger",
+ "folder_compare",
  "graphviz-rust",
  "log",
  "pulldown-cmark",
@@ -406,7 +427,7 @@ dependencies = [
  "pest_meta",
  "proc-macro2",
  "quote",
- "syn 2.0.87",
+ "syn 2.0.89",
 ]
 
 [[package]]
@@ -431,9 +452,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.89"
+version = "1.0.91"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f139b0662de085916d1fb67d2b4169d1addddda1919e696f3252b740b629986e"
+checksum = "307e3004becf10f5a6e0d59d20f3cd28231b0e0827a96cd3e0ce6d14bc1e4bb3"
 dependencies = [
  "unicode-ident",
 ]
@@ -520,9 +541,9 @@ checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 
 [[package]]
 name = "rustix"
-version = "0.38.40"
+version = "0.38.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "99e4ea3e1cdc4b559b8e5650f9c8e5998e3e5c1343b4eaf034565f32318d63c0"
+checksum = "d7f649912bc1495e167a6edee79151c84b1bad49748cb4f1f1167f459f6224f6"
 dependencies = [
  "bitflags",
  "errno",
@@ -531,6 +552,15 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "serde"
 version = "1.0.215"
@@ -548,7 +578,7 @@ checksum = "ad1e866f866923f252f05c889987993144fb74e722403468a4ebd70c3cd756c0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.87",
+ "syn 2.0.89",
 ]
 
 [[package]]
@@ -590,9 +620,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.87"
+version = "2.0.89"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "25aa4ce346d03a6dcd68dd8b4010bcb74e54e62c90c573f394c46eae99aba32d"
+checksum = "44d46482f1c1c87acd84dea20c1bf5ebff4c757009ed6bf19cfd36fb10e92c4e"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -638,7 +668,7 @@ checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.87",
+ "syn 2.0.89",
 ]
 
 [[package]]
@@ -695,9 +725,9 @@ checksum = "7e51b68083f157f853b6379db119d1c1be0e6e4dec98101079dec41f6f5cf6df"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.13"
+version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
+checksum = "adb9e6ca4f869e1180728b7950e35922a7fc6397f7b641499e8f3ef06e50dc83"
 
 [[package]]
 name = "unicode-width"
@@ -717,6 +747,16 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
+[[package]]
+name = "walkdir"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "29790946404f91d9c5d06f9874efddea1dc06c5efe94541a7d6863108e3a5e4b"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
@@ -841,5 +881,5 @@ checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.87",
+ "syn 2.0.89",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 23c4f05..6b6d6fb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,6 +21,9 @@ serde = {version = "1", features = ["derive"]}
 thiserror = "1"
 toml = "0.7"
 
+[dev-dependencies]
+folder_compare = "0.4.0"
+
 # The profile that 'cargo dist' will build with
 [profile.dist]
 inherits = "release"
diff --git a/tests/.gitignore b/tests/.gitignore
new file mode 100644
index 0000000..ed8f613
--- /dev/null
+++ b/tests/.gitignore
@@ -0,0 +1 @@
+data_out
diff --git a/tests/data_in/.gitignore b/tests/data_in/.gitignore
new file mode 100644
index 0000000..7585238
--- /dev/null
+++ b/tests/data_in/.gitignore
@@ -0,0 +1 @@
+book
diff --git a/tests/data_in/book.toml b/tests/data_in/book.toml
new file mode 100644
index 0000000..d5c3944
--- /dev/null
+++ b/tests/data_in/book.toml
@@ -0,0 +1,6 @@
+[book]
+authors = ["Jonathan Pallant"]
+language = "en"
+multilingual = false
+src = "src"
+title = "Sample Book"
diff --git a/tests/data_in/index_template.html b/tests/data_in/index_template.html
new file mode 100644
index 0000000..5319ffb
--- /dev/null
+++ b/tests/data_in/index_template.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<title>$TITLE</title>
+</head>
+<body class="article">
+<h1>$TITLE</h1>
+<div>
+$INDEX
+</div>
+</body>
+</html>
diff --git a/tests/data_in/src/SUMMARY.md b/tests/data_in/src/SUMMARY.md
new file mode 100644
index 0000000..fa67cf3
--- /dev/null
+++ b/tests/data_in/src/SUMMARY.md
@@ -0,0 +1,4 @@
+# Summary
+
+- [Chapter 1](./chapter_1.md)
+- [Chapter 2](./chapter_2.md)
diff --git a/tests/data_in/src/chapter_1.md b/tests/data_in/src/chapter_1.md
new file mode 100644
index 0000000..7264736
--- /dev/null
+++ b/tests/data_in/src/chapter_1.md
@@ -0,0 +1,9 @@
+# Page 1
+
+## Page 2
+
+---
+
+Page 3
+
+## Page 4
diff --git a/tests/data_in/src/chapter_2.md b/tests/data_in/src/chapter_2.md
new file mode 100644
index 0000000..b632ee7
--- /dev/null
+++ b/tests/data_in/src/chapter_2.md
@@ -0,0 +1,10 @@
+# Page 1
+
+```dot process
+digraph {
+    node [shape=record];
+    "X";
+}
+```
+
+## Page 2
diff --git a/tests/data_in/template.html b/tests/data_in/template.html
new file mode 100644
index 0000000..fac1de3
--- /dev/null
+++ b/tests/data_in/template.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<title>$TITLE</title>
+</head>
+<body>
+<section data-markdown>
+<textarea data-template>
+$CONTENT
+</textarea>
+</section>
+</body>
+</html>
diff --git a/tests/data_out/.keep b/tests/data_out/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/tests/reference.rs b/tests/reference.rs
new file mode 100644
index 0000000..aa11214
--- /dev/null
+++ b/tests/reference.rs
@@ -0,0 +1,44 @@
+//! Builds a reference book into a set of slides, and checks they match what we expect.
+
+use std::path::Path;
+
+#[test]
+fn build_slides() {
+    let slide_template_string = include_str!("./data_in/template.html");
+    let index_template_string = include_str!("./data_in/index_template.html");
+    println!("We are in: {}", std::env::current_dir().unwrap().display());
+    mdslides::run(
+        Some(Path::new("tests/data_in")),
+        Path::new("tests/data_out"),
+        slide_template_string,
+        Some(index_template_string),
+    )
+    .expect("mdslides failed");
+
+    let comparison = folder_compare::FolderCompare::new(
+        Path::new("tests/reference_out"),
+        Path::new("tests/data_out"),
+        &vec![],
+    )
+    .expect("failed to compare");
+    if !comparison.changed_files.is_empty() {
+        for filename in comparison.changed_files {
+            let contents = std::fs::read_to_string(&filename).unwrap();
+            eprintln!(
+                "Changed File {filename}:\n{contents}",
+                filename = filename.display()
+            );
+        }
+        panic!("Some files differ");
+    }
+    if !comparison.new_files.is_empty() {
+        for filename in comparison.new_files {
+            let contents = std::fs::read_to_string(&filename).unwrap();
+            eprintln!(
+                "New File {filename}:\n{contents}",
+                filename = filename.display()
+            );
+        }
+        panic!("Some new files found");
+    }
+}
diff --git a/tests/reference_out/chapter_1.html b/tests/reference_out/chapter_1.html
new file mode 100644
index 0000000..53521a5
--- /dev/null
+++ b/tests/reference_out/chapter_1.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<title>Chapter 1</title>
+</head>
+<body>
+<section data-markdown>
+<textarea data-template>
+# Page 1
+
+---
+## Page 2
+
+---
+
+Page 3
+
+---
+## Page 4
+
+</textarea>
+</section>
+</body>
+</html>
diff --git a/tests/reference_out/chapter_2.html b/tests/reference_out/chapter_2.html
new file mode 100644
index 0000000..919f524
--- /dev/null
+++ b/tests/reference_out/chapter_2.html
@@ -0,0 +1,38 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<title>Chapter 2</title>
+</head>
+<body>
+<section data-markdown>
+<textarea data-template>
+# Page 1
+
+<figure>
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
+ "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<!-- Generated by graphviz version 12.2.0 (20241103.1931)
+ -->
+<!-- Pages: 1 -->
+<svg width="62pt" height="45pt"
+ viewBox="0.00 0.00 62.00 45.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 41)">
+<polygon fill="white" stroke="none" points="-4,4 -4,-41 58,-41 58,4 -4,4"/>
+<!-- X -->
+<g id="node1" class="node">
+<title>X</title>
+<polygon fill="none" stroke="black" points="0,-0.5 0,-36.5 54,-36.5 54,-0.5 0,-0.5"/>
+<text text-anchor="middle" x="26.88" y="-13.45" font-family="Times,serif" font-size="14.00">X</text>
+</g>
+</g>
+</svg>
+</figure>
+
+---
+## Page 2
+
+</textarea>
+</section>
+</body>
+</html>
diff --git a/tests/reference_out/index.html b/tests/reference_out/index.html
new file mode 100644
index 0000000..dde97a2
--- /dev/null
+++ b/tests/reference_out/index.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<title>Sample Book</title>
+</head>
+<body class="article">
+<h1>Sample Book</h1>
+<div>
+<h1>Summary</h1>
+<ul>
+<li><a href="./chapter_1.html">Chapter 1</a></li>
+<li><a href="./chapter_2.html">Chapter 2</a></li>
+</ul>
+
+</div>
+</body>
+</html>

From 3cfffb2e0dc2ff7bfcf289366fa0bb956a589889 Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Thu, 21 Nov 2024 10:54:23 +0000
Subject: [PATCH 5/6] Show me the test results the other way around.

Showing me the reference file isn't useful - I have that file. I need to see the generated file in data_out.
---
 tests/reference.rs        | 2 +-
 tests/reference_out/.keep | 0
 2 files changed, 1 insertion(+), 1 deletion(-)
 create mode 100644 tests/reference_out/.keep

diff --git a/tests/reference.rs b/tests/reference.rs
index aa11214..326c5cb 100644
--- a/tests/reference.rs
+++ b/tests/reference.rs
@@ -16,8 +16,8 @@ fn build_slides() {
     .expect("mdslides failed");
 
     let comparison = folder_compare::FolderCompare::new(
-        Path::new("tests/reference_out"),
         Path::new("tests/data_out"),
+        Path::new("tests/reference_out"),
         &vec![],
     )
     .expect("failed to compare");
diff --git a/tests/reference_out/.keep b/tests/reference_out/.keep
new file mode 100644
index 0000000..e69de29

From 6ed73c3aef1579873ed310bf0d3058a859d7baf7 Mon Sep 17 00:00:00 2001
From: Jonathan Pallant <jonathan.pallant@ferrous-systems.com>
Date: Thu, 21 Nov 2024 12:00:37 +0000
Subject: [PATCH 6/6] Re-capture reference output using graphviz from Github CI

---
 tests/data_in/template.html        |  4 ----
 tests/reference_out/chapter_1.html |  4 ----
 tests/reference_out/chapter_2.html | 13 +++++--------
 3 files changed, 5 insertions(+), 16 deletions(-)

diff --git a/tests/data_in/template.html b/tests/data_in/template.html
index fac1de3..7f0f3e8 100644
--- a/tests/data_in/template.html
+++ b/tests/data_in/template.html
@@ -4,10 +4,6 @@
 <title>$TITLE</title>
 </head>
 <body>
-<section data-markdown>
-<textarea data-template>
 $CONTENT
-</textarea>
-</section>
 </body>
 </html>
diff --git a/tests/reference_out/chapter_1.html b/tests/reference_out/chapter_1.html
index 53521a5..d115a3a 100644
--- a/tests/reference_out/chapter_1.html
+++ b/tests/reference_out/chapter_1.html
@@ -4,8 +4,6 @@
 <title>Chapter 1</title>
 </head>
 <body>
-<section data-markdown>
-<textarea data-template>
 # Page 1
 
 ---
@@ -18,7 +16,5 @@
 ---
 ## Page 4
 
-</textarea>
-</section>
 </body>
 </html>
diff --git a/tests/reference_out/chapter_2.html b/tests/reference_out/chapter_2.html
index 919f524..792ff08 100644
--- a/tests/reference_out/chapter_2.html
+++ b/tests/reference_out/chapter_2.html
@@ -4,26 +4,25 @@
 <title>Chapter 2</title>
 </head>
 <body>
-<section data-markdown>
-<textarea data-template>
 # Page 1
 
 <figure>
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<!-- Generated by graphviz version 12.2.0 (20241103.1931)
+<!-- Generated by graphviz version 2.43.0 (0)
  -->
-<!-- Pages: 1 -->
+<!-- Title: %3 Pages: 1 -->
 <svg width="62pt" height="45pt"
  viewBox="0.00 0.00 62.00 45.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
 <g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 41)">
-<polygon fill="white" stroke="none" points="-4,4 -4,-41 58,-41 58,4 -4,4"/>
+<title>%3</title>
+<polygon fill="white" stroke="transparent" points="-4,4 -4,-41 58,-41 58,4 -4,4"/>
 <!-- X -->
 <g id="node1" class="node">
 <title>X</title>
 <polygon fill="none" stroke="black" points="0,-0.5 0,-36.5 54,-36.5 54,-0.5 0,-0.5"/>
-<text text-anchor="middle" x="26.88" y="-13.45" font-family="Times,serif" font-size="14.00">X</text>
+<text text-anchor="middle" x="27" y="-14.8" font-family="Times,serif" font-size="14.00">X</text>
 </g>
 </g>
 </svg>
@@ -32,7 +31,5 @@
 ---
 ## Page 2
 
-</textarea>
-</section>
 </body>
 </html>