mirror of https://github.com/jkjoy/sunpeiwen.git
121 lines
3.2 KiB
JavaScript
121 lines
3.2 KiB
JavaScript
'use strict';
|
|
|
|
module.exports = walkAST;
|
|
function walkAST(ast, before, after, options) {
|
|
if (after && typeof after === 'object' && typeof options === 'undefined') {
|
|
options = after;
|
|
after = null;
|
|
}
|
|
options = options || {includeDependencies: false};
|
|
var parents = (options.parents = options.parents || []);
|
|
|
|
var replace = function replace(replacement) {
|
|
if (Array.isArray(replacement) && !replace.arrayAllowed) {
|
|
throw new Error(
|
|
'replace() can only be called with an array if the last parent is a Block or NamedBlock'
|
|
);
|
|
}
|
|
ast = replacement;
|
|
};
|
|
replace.arrayAllowed =
|
|
parents[0] &&
|
|
(/^(Named)?Block$/.test(parents[0].type) ||
|
|
(parents[0].type === 'RawInclude' && ast.type === 'IncludeFilter'));
|
|
|
|
if (before) {
|
|
var result = before(ast, replace);
|
|
if (result === false) {
|
|
return ast;
|
|
} else if (Array.isArray(ast)) {
|
|
// return right here to skip after() call on array
|
|
return walkAndMergeNodes(ast);
|
|
}
|
|
}
|
|
|
|
parents.unshift(ast);
|
|
|
|
switch (ast.type) {
|
|
case 'NamedBlock':
|
|
case 'Block':
|
|
ast.nodes = walkAndMergeNodes(ast.nodes);
|
|
break;
|
|
case 'Case':
|
|
case 'Filter':
|
|
case 'Mixin':
|
|
case 'Tag':
|
|
case 'InterpolatedTag':
|
|
case 'When':
|
|
case 'Code':
|
|
case 'While':
|
|
if (ast.block) {
|
|
ast.block = walkAST(ast.block, before, after, options);
|
|
}
|
|
break;
|
|
case 'Each':
|
|
if (ast.block) {
|
|
ast.block = walkAST(ast.block, before, after, options);
|
|
}
|
|
if (ast.alternate) {
|
|
ast.alternate = walkAST(ast.alternate, before, after, options);
|
|
}
|
|
break;
|
|
case 'EachOf':
|
|
if (ast.block) {
|
|
ast.block = walkAST(ast.block, before, after, options);
|
|
}
|
|
break;
|
|
case 'Conditional':
|
|
if (ast.consequent) {
|
|
ast.consequent = walkAST(ast.consequent, before, after, options);
|
|
}
|
|
if (ast.alternate) {
|
|
ast.alternate = walkAST(ast.alternate, before, after, options);
|
|
}
|
|
break;
|
|
case 'Include':
|
|
walkAST(ast.block, before, after, options);
|
|
walkAST(ast.file, before, after, options);
|
|
break;
|
|
case 'Extends':
|
|
walkAST(ast.file, before, after, options);
|
|
break;
|
|
case 'RawInclude':
|
|
ast.filters = walkAndMergeNodes(ast.filters);
|
|
walkAST(ast.file, before, after, options);
|
|
break;
|
|
case 'Attrs':
|
|
case 'BlockComment':
|
|
case 'Comment':
|
|
case 'Doctype':
|
|
case 'IncludeFilter':
|
|
case 'MixinBlock':
|
|
case 'YieldBlock':
|
|
case 'Text':
|
|
break;
|
|
case 'FileReference':
|
|
if (options.includeDependencies && ast.ast) {
|
|
walkAST(ast.ast, before, after, options);
|
|
}
|
|
break;
|
|
default:
|
|
throw new Error('Unexpected node type ' + ast.type);
|
|
break;
|
|
}
|
|
|
|
parents.shift();
|
|
|
|
after && after(ast, replace);
|
|
return ast;
|
|
|
|
function walkAndMergeNodes(nodes) {
|
|
return nodes.reduce(function(nodes, node) {
|
|
var result = walkAST(node, before, after, options);
|
|
if (Array.isArray(result)) {
|
|
return nodes.concat(result);
|
|
} else {
|
|
return nodes.concat([result]);
|
|
}
|
|
}, []);
|
|
}
|
|
}
|