Fixes #791 - resolves imports in-memory if possible.

Why:

* When a hash is given as a source, some imports can be inlined
  in-memory taking styles from the hash.

History.md

@@ -14,6 +14,7 @@
 * Fixed issue [#686](https:/jakubpawlowicz/clean-css/issues/686) - adds rounding precision for all units.
 * Fixed issue [#756](https:/jakubpawlowicz/clean-css/issues/756) - adds disabling font-weight optimizations.
 * Fixed issue [#758](https:/jakubpawlowicz/clean-css/issues/758) - ignores rules with empty selector.
+* Fixed issue [#791](https:/jakubpawlowicz/clean-css/issues/791) - resolves imports in-memory if possible.
 * Fixed issue [#817](https:/jakubpawlowicz/clean-css/issues/817) - makes `off` disable rounding.
 * Fixed issue [#818](https:/jakubpawlowicz/clean-css/issues/818) - disables `px` rounding by default.
 * Fixed issue [#834](https:/jakubpawlowicz/clean-css/issues/834) - adds extra line break in nested blocks.

README.md

@@ -317,6 +317,8 @@ new CleanCSS().minify({
 });
 ```
 
+Important note - any `@import` rules already present in the hash will be automatically resolved in memory.
+
 ### How to set a compatibility mode?
 
 Compatibility settings are controlled by `--compatibility` switch (CLI) and `compatibility` option (library mode).

lib/reader/is-already-loaded.js

@@ -0,0 +1,11 @@
+var restoreImport = require('./restore-import');
+
+var Marker = require('../tokenizer/marker');
+
+function isAlreadyLoaded(uri, sourcesContent) {
+ // the second check is because clean-css accepts an array of input file paths
+ // which are internally transformed into imports
+ return uri in sourcesContent && sourcesContent[uri] != (restoreImport(uri, '') + Marker.SEMICOLON);
+}
+
+module.exports = isAlreadyLoaded;

lib/reader/read-sources.js

@@ -4,6 +4,7 @@ var path = require('path');
 var applySourceMaps = require('./apply-source-maps');
 var extractImportUrlAndMedia = require('./extract-import-url-and-media');
 var isAllowedResource = require('./is-allowed-resource');
+var isAlreadyLoaded = require('./is-already-loaded');
 var loadOriginalSources = require('./load-original-sources');
 var loadRemoteResource = require('./load-remote-resource');
 var rebase = require('./rebase');
@@ -13,6 +14,7 @@ var restoreImport = require('./restore-import');
 
 var tokenize = require('../tokenizer/tokenize');
 var Token = require('../tokenizer/token');
+var Marker = require('../tokenizer/marker');
 var isAbsoluteResource = require('../utils/is-absolute-resource');
 var isImport = require('../utils/is-import');
 var isRemoteResource = require('../utils/is-remote-resource');
@@ -62,7 +64,7 @@ function fromArray(input, context, parentInlinerContext, callback) {
 
  if (isRemoteResource(uri)) {
  accumulator[uri] = {
- styles: restoreImport(uri, '') + ';'
+ styles: restoreImport(uri, '') + Marker.SEMICOLON
  };
  } else if (!fs.existsSync(absoluteUri) || !fs.statSync(absoluteUri).isFile()) {
  context.errors.push('Ignoring "' + absoluteUri + '" as resource is missing.');
@@ -83,13 +85,15 @@ function fromHash(input, context, parentInlinerContext, callback) {
  var tokens = [];
  var newTokens = [];
  var uri;
+ var realUri;
  var source;
  var parsedMap;
  var rebasedMap;
  var rebaseConfig;
 
  for (uri in input) {
  source = input[uri];
+ realUri = uri == UNKNOWN_URI ? undefined : uri;
 
  if (source.sourceMap) {
  parsedMap = typeof source.sourceMap == 'string' ?
@@ -98,12 +102,15 @@ function fromHash(input, context, parentInlinerContext, callback) {
  rebasedMap = isRemoteResource(uri) ?
  rebaseRemoteMap(parsedMap, uri) :
  rebaseLocalMap(parsedMap, uri, context.options.rebaseTo);
- context.inputSourceMapTracker.track(uri == UNKNOWN_URI ? undefined : uri, rebasedMap);
+ context.inputSourceMapTracker.track(realUri, rebasedMap);
  }
 
- context.source = uri !== UNKNOWN_URI ? uri : undefined;
-  context.sourcesContent[context.source] = source.styles;
+ context.sourcesContent[realUri] = source.styles;
+ }
 
+ for (uri in input) {
+ source = input[uri];
+ realUri = uri == UNKNOWN_URI ? undefined : uri;
  rebaseConfig = {};
 
  if (uri == UNKNOWN_URI) {
@@ -120,6 +127,8 @@ function fromHash(input, context, parentInlinerContext, callback) {
  rebaseConfig.toBase = context.options.rebaseTo;
  }
 
+ context.source = realUri;
+
  newTokens = tokenize(source.styles, context);
  newTokens = rebase(newTokens, context.options.rebase, context.validator, rebaseConfig);
 
@@ -189,6 +198,7 @@ function inlineStylesheet(token, inlinerContext) {
 function inlineRemoteStylesheet(uri, mediaQuery, metadata, inlinerContext) {
  var isAllowed = isAllowedResource(uri, true, inlinerContext.processImportFrom);
  var originalUri = uri;
+ var isLoaded = isAlreadyLoaded(uri, inlinerContext.externalContext.sourcesContent);
 
  if (inlinerContext.inlinedStylesheets.indexOf(uri) > -1) {
  inlinerContext.warnings.push('Ignoring remote @import of "' + uri + '" as it has already been imported.');
@@ -198,7 +208,7 @@ function inlineRemoteStylesheet(uri, mediaQuery, metadata, inlinerContext) {
  inlinerContext.warnings.push('Ignoring remote @import of "' + uri + '" as no callback given and after other content.');
  inlinerContext.sourceTokens = inlinerContext.sourceTokens.slice(1);
  return doInlineImports(inlinerContext);
- } else if (inlinerContext.localOnly) {
+ } else if (inlinerContext.localOnly && !isLoaded) {
  inlinerContext.warnings.push('Skipping remote @import of "' + uri + '" as no callback given.');
  inlinerContext.outputTokens = inlinerContext.outputTokens.concat(inlinerContext.sourceTokens.slice(0, 1));
  inlinerContext.sourceTokens = inlinerContext.sourceTokens.slice(1);
@@ -216,7 +226,7 @@ function inlineRemoteStylesheet(uri, mediaQuery, metadata, inlinerContext) {
 
  inlinerContext.inlinedStylesheets.push(uri);
 
- loadRemoteResource(uri, inlinerContext.inlinerOptions, function (error, importedStyles) {
+ function whenLoaded(error, importedStyles) {
  var sourceHash = {};
 
  if (error) {
@@ -233,6 +243,7 @@ function inlineRemoteStylesheet(uri, mediaQuery, metadata, inlinerContext) {
  styles: importedStyles
  };
 
+ inlinerContext.externalContext.sourcesContent[uri] = importedStyles;
  inlinerContext.isRemote = true;
  fromHash(sourceHash, inlinerContext.externalContext, inlinerContext, function (importedTokens) {
  importedTokens = wrapInMedia(importedTokens, mediaQuery, metadata);
@@ -242,7 +253,11 @@ function inlineRemoteStylesheet(uri, mediaQuery, metadata, inlinerContext) {
 
  doInlineImports(inlinerContext);
  });
- });
+ }
+
+ return isLoaded ?
+ whenLoaded(null, inlinerContext.externalContext.sourcesContent[uri]) :
+ loadRemoteResource(uri, inlinerContext.inlinerOptions, whenLoaded);
 }
 
 function inlineLocalStylesheet(uri, mediaQuery, metadata, inlinerContext) {
@@ -255,10 +270,11 @@ function inlineLocalStylesheet(uri, mediaQuery, metadata, inlinerContext) {
  var importedTokens;
  var isAllowed = isAllowedResource(uri, false, inlinerContext.processImportFrom);
  var sourceHash = {};
+ var isLoaded = isAlreadyLoaded(relativeToCurrentPath, inlinerContext.externalContext.sourcesContent);
 
  if (inlinerContext.inlinedStylesheets.indexOf(absoluteUri) > -1) {
  inlinerContext.warnings.push('Ignoring local @import of "' + uri + '" as it has already been imported.');
- } else if (!fs.existsSync(absoluteUri) || !fs.statSync(absoluteUri).isFile()) {
+ } else if (!isLoaded && !fs.existsSync(absoluteUri) || !fs.statSync(absoluteUri).isFile()) {
  inlinerContext.errors.push('Ignoring local @import of "' + uri + '" as resource is missing.');
  } else if (!isAllowed && inlinerContext.afterContent) {
  inlinerContext.warnings.push('Ignoring local @import of "' + uri + '" as resource is not allowed and after other content.');
@@ -268,12 +284,16 @@ function inlineLocalStylesheet(uri, mediaQuery, metadata, inlinerContext) {
  inlinerContext.warnings.push('Skipping local @import of "' + uri + '" as resource is not allowed.');
  inlinerContext.outputTokens = inlinerContext.outputTokens.concat(inlinerContext.sourceTokens.slice(0, 1));
  } else {
- importedStyles = fs.readFileSync(absoluteUri, 'utf-8');
+ importedStyles = isLoaded ?
+ inlinerContext.externalContext.sourcesContent[relativeToCurrentPath] :
+ fs.readFileSync(absoluteUri, 'utf-8');
  inlinerContext.inlinedStylesheets.push(absoluteUri);
 
  sourceHash[relativeToCurrentPath] = {
  styles: importedStyles
  };
+ inlinerContext.externalContext.sourcesContent[relativeToCurrentPath] = importedStyles;
+
  importedTokens = fromHash(sourceHash, inlinerContext.externalContext, inlinerContext, function (tokens) { return tokens; });
  importedTokens = wrapInMedia(importedTokens, mediaQuery, metadata);
 

test/module-test.js

@@ -635,6 +635,24 @@ vows.describe('module tests').addBatch({
  'gives right output': function (minified) {
  assert.equal(minified.styles, 'div{background-image:url(http://127.0.0.1/image.png)}');
  }
+ },
+ 'with already resolved imports': {
+ 'topic': function () {
+ new CleanCSS().minify({
+ 'main.css': {
+ styles: '@import url(test/fixtures/partials/one.css);\n@import url(http://127.0.0.1/test.css);'
+ },
+ 'test/fixtures/partials/one.css': {
+ styles: '.one { background-color:#f00; }'
+ },
+ 'http://127.0.0.1/test.css': {
+ styles: '.test { color: #000 }'
+ }
+ }, this.callback);
+ },
+ 'gives right output without reading resources': function (minified) {
+ assert.equal(minified.styles, '.one{background-color:red}.test{color:#000}');
+ }
  }
  }
 }).export(module);