GRIT: Enable variable expansion in filenames during HTML inlining.

BUG=232048
R=flackr@chromium.org

Review URL: https://codereview.chromium.org/16539002

git-svn-id: http://grit-i18n.googlecode.com/svn/trunk@125 7262f16d-afe8-6277-6482-052fa10e57b1

8 files changed, 216 insertions, 38 deletions

diff --git a/grit/format/html_inline.py b/grit/format/html_inline.py
index 569c282..b5e0b0f 100755
--- a/grit/format/html_inline.py
+++ b/grit/format/html_inline.py
@@ -72,7 +72,8 @@ def GetDistribution():
 
 
 def SrcInlineAsDataURL(
-    src_match, base_path, distribution, inlined_files, names_only=False):
+    src_match, base_path, distribution, inlined_files, names_only=False,
+    filename_expansion_function=None):
   """regex replace function.
 
   Takes a regex match for src="filename", attempts to read the file
@@ -93,6 +94,8 @@ def SrcInlineAsDataURL(
     string
   """
   filename = src_match.group('filename')
+  if filename_expansion_function:
+    filename = filename_expansion_function(filename)
   quote = src_match.group('quote')
 
   if filename.find(':') != -1:
@@ -126,7 +129,7 @@ class InlinedData:
 
 def DoInline(
     input_filename, grd_node, allow_external_script=False, names_only=False,
-    rewrite_function=None):
+    rewrite_function=None, filename_expansion_function=None):
   """Helper function that inlines the resources in a specified file.
 
   Reads input_filename, finds all the src attributes and attempts to
@@ -139,10 +142,14 @@ def DoInline(
     names_only: |nil| will be returned for the inlined contents (faster).
     rewrite_function: function(filepath, text, distribution) which will be
         called to rewrite html content before inlining images.
+    filename_expansion_function: function(filename) which will be called to
+        rewrite filenames before attempting to read them.
   Returns:
     a tuple of the inlined data as a string and the set of filenames
     of all the inlined files
   """
+  if filename_expansion_function:
+    input_filename = filename_expansion_function(input_filename)
   input_filepath = os.path.dirname(input_filename)
   distribution = GetDistribution()
 
@@ -153,7 +160,8 @@ def DoInline(
                  inlined_files=inlined_files):
     """Helper function to provide SrcInlineAsDataURL with the base file path"""
     return SrcInlineAsDataURL(
-        src_match, filepath, distribution, inlined_files, names_only=names_only)
+        src_match, filepath, distribution, inlined_files, names_only=names_only,
+        filename_expansion_function=filename_expansion_function)
 
   def GetFilepath(src_match, base_path = input_filepath):
     filename = src_match.group('filename')
@@ -163,6 +171,8 @@ def DoInline(
       return None
 
     filename = filename.replace('%DISTRIBUTION%', distribution)
+    if filename_expansion_function:
+      filename = filename_expansion_function(filename)
     return os.path.normpath(os.path.join(base_path, filename))
 
   def IsConditionSatisfied(src_match):
@@ -214,12 +224,16 @@ def DoInline(
     inlined_files.add(filepath)
 
     if names_only:
-      inlined_files.update(GetResourceFilenames(filepath,
-                                                allow_external_script,
-                                                rewrite_function))
+      inlined_files.update(GetResourceFilenames(
+          filepath,
+          allow_external_script,
+          rewrite_function,
+          filename_expansion_function=filename_expansion_function))
       return ""
 
-    return pattern % InlineToString(filepath, grd_node, allow_external_script)
+    return pattern % InlineToString(
+        filepath, grd_node, allow_external_script,
+        filename_expansion_function=filename_expansion_function)
 
   def InlineIncludeFiles(src_match):
     """Helper function to directly inline generic external files (without
@@ -338,7 +352,7 @@ def DoInline(
 
 
 def InlineToString(input_filename, grd_node, allow_external_script=False,
-                   rewrite_function=None):
+                   rewrite_function=None, filename_expansion_function=None):
   """Inlines the resources in a specified file and returns it as a string.
 
   Args:
@@ -348,10 +362,12 @@ def InlineToString(input_filename, grd_node, allow_external_script=False,
     the inlined data as a string
   """
   try:
-    return DoInline(input_filename,
-                    grd_node,
-                    allow_external_script=allow_external_script,
-                    rewrite_function=rewrite_function).inlined_data
+    return DoInline(
+        input_filename,
+        grd_node,
+        allow_external_script=allow_external_script,
+        rewrite_function=rewrite_function,
+        filename_expansion_function=filename_expansion_function).inlined_data
   except IOError, e:
     raise Exception("Failed to open %s while trying to flatten %s. (%s)" %
                     (e.filename, input_filename, e.strerror))
@@ -378,14 +394,17 @@ def InlineToFile(input_filename, output_filename, grd_node):
 
 def GetResourceFilenames(filename,
                          allow_external_script=False,
-                         rewrite_function=None):
+                         rewrite_function=None,
+                         filename_expansion_function=None):
   """For a grd file, returns a set of all the files that would be inline."""
   try:
-    return DoInline(filename,
-                    None,
-                    names_only=True,
-                    allow_external_script=allow_external_script,
-                    rewrite_function=rewrite_function).inlined_files
+    return DoInline(
+        filename,
+        None,
+        names_only=True,
+        allow_external_script=allow_external_script,
+        rewrite_function=rewrite_function,
+        filename_expansion_function=filename_expansion_function).inlined_files
   except IOError, e:
     raise Exception("Failed to open %s while trying to flatten %s. (%s)" %
                     (e.filename, filename, e.strerror))
diff --git a/grit/format/html_inline_unittest.py b/grit/format/html_inline_unittest.py
index 7d546a5..45840f2 100755
--- a/grit/format/html_inline_unittest.py
+++ b/grit/format/html_inline_unittest.py
@@ -202,6 +202,66 @@ class HtmlInlineUnittest(unittest.TestCase):
     self.failUnlessEqual(expected_inlined,
                          util.FixLineEnd(result.inlined_data, '\n'))
 
+  def testFilenameVariableExpansion(self):
+    '''Tests that variables are expanded in filenames before inlining.'''
+
+    files = {
+      'index.html': '''
+      <html>
+      <head>
+      <link rel="stylesheet" href="style[WHICH].css">
+      <script src="script[WHICH].js"></script>
+      </head>
+      <include src="tmpl[WHICH].html">
+      <img src="img[WHICH].png">
+      </html>
+      ''',
+      'style1.css': '''h1 {}''',
+      'tmpl1.html': '''<h1></h1>''',
+      'script1.js': '''console.log('hello');''',
+      'img1.png': '''abc''',
+    }
+
+    expected_inlined = '''
+      <html>
+      <head>
+      <style>h1 {}</style>
+      <script>console.log('hello');</script>
+      </head>
+      <h1></h1>
+      <img src="data:image/png;base64,YWJj">
+      </html>
+      '''
+
+    source_resources = set()
+    tmp_dir = util.TempDir(files)
+    for filename in files:
+      source_resources.add(tmp_dir.GetPath(filename))
+
+    def replacer(var, repl):
+      return lambda filename: filename.replace('[%s]' % var, repl)
+
+    # Test normal inlining.
+    result = html_inline.DoInline(
+        tmp_dir.GetPath('index.html'),
+        None,
+        filename_expansion_function=replacer('WHICH', '1'))
+    resources = result.inlined_files
+    resources.add(tmp_dir.GetPath('index.html'))
+    self.failUnlessEqual(resources, source_resources)
+    self.failUnlessEqual(expected_inlined,
+                         util.FixLineEnd(result.inlined_data, '\n'))
+
+    # Test names-only inlining.
+    result = html_inline.DoInline(
+        tmp_dir.GetPath('index.html'),
+        None,
+        names_only=True,
+        filename_expansion_function=replacer('WHICH', '1'))
+    resources = result.inlined_files
+    resources.add(tmp_dir.GetPath('index.html'))
+    self.failUnlessEqual(resources, source_resources)
+
 
 if __name__ == '__main__':
   unittest.main()
diff --git a/grit/gather/chrome_html.py b/grit/gather/chrome_html.py
index d5a2b07..d554776 100644
--- a/grit/gather/chrome_html.py
+++ b/grit/gather/chrome_html.py
@@ -48,7 +48,8 @@ _HTML_IMAGE_SRC = lazy_re.compile(
     '<img[^>]+src=\"(?P<filename>[^">]*)\"[^>]*>')
 
 def GetImageList(
-    base_path, filename, scale_factors, distribution):
+    base_path, filename, scale_factors, distribution,
+    filename_expansion_function=None):
   """Generate the list of images which match the provided scale factors.
 
   Takes an image filename and checks for files of the same name in folders
@@ -79,6 +80,8 @@ def GetImageList(
     return [('1x', filename)]
 
   filename = filename.replace(DIST_SUBSTR, distribution)
+  if filename_expansion_function:
+    filename = filename_expansion_function(filename)
   filepath = os.path.join(base_path, filename)
   images = [('1x', filename)]
 
@@ -114,7 +117,8 @@ def GenerateImageSet(images, quote):
 
 
 def InsertImageSet(
-    src_match, base_path, scale_factors, distribution):
+    src_match, base_path, scale_factors, distribution,
+    filename_expansion_function=None):
   """Regex replace function which inserts -webkit-image-set.
 
   Takes a regex match for url('path'). If the file is local, checks for
@@ -136,7 +140,9 @@ def InsertImageSet(
   quote = src_match.group('quote')
   filename = src_match.group('filename')
   attr = src_match.group('attribute')
-  image_list = GetImageList(base_path, filename, scale_factors, distribution)
+  image_list = GetImageList(
+      base_path, filename, scale_factors, distribution,
+      filename_expansion_function=filename_expansion_function)
 
   # Don't modify the source if there is only one image.
   if len(image_list) == 1:
@@ -146,14 +152,17 @@ def InsertImageSet(
 
 
 def InsertImageStyle(
-    src_match, base_path, scale_factors, distribution):
+    src_match, base_path, scale_factors, distribution,
+    filename_expansion_function=None):
   """Regex replace function which adds a content style to an <img>.
 
   Takes a regex match from _HTML_IMAGE_SRC and replaces the attribute with a CSS
   style which defines the image set.
   """
   filename = src_match.group('filename')
-  image_list = GetImageList(base_path, filename, scale_factors, distribution)
+  image_list = GetImageList(
+      base_path, filename, scale_factors, distribution,
+      filename_expansion_function=filename_expansion_function)
 
   # Don't modify the source if there is only one image or image already defines
   # a style.
@@ -165,16 +174,21 @@ def InsertImageStyle(
 
 
 def InsertImageSets(
-    filepath, text, scale_factors, distribution):
+    filepath, text, scale_factors, distribution,
+    filename_expansion_function=None):
   """Helper function that adds references to external images available in any of
   scale_factors in CSS backgrounds.
   """
   # Add high DPI urls for css attributes: content, background,
   # or *-image or <img src="foo">.
   return _CSS_IMAGE_URLS.sub(
-      lambda m: InsertImageSet(m, filepath, scale_factors, distribution),
+      lambda m: InsertImageSet(
+          m, filepath, scale_factors, distribution,
+          filename_expansion_function=filename_expansion_function),
       _HTML_IMAGE_SRC.sub(
-          lambda m: InsertImageStyle(m, filepath, scale_factors, distribution),
+          lambda m: InsertImageStyle(
+              m, filepath, scale_factors, distribution,
+              filename_expansion_function=filename_expansion_function),
           text)).decode('utf-8').encode('utf-8')
 
 
@@ -208,17 +222,20 @@ def RemoveImageSetImages(text, scale_factors):
 
 
 def ProcessImageSets(
-    filepath, text, scale_factors, distribution):
+    filepath, text, scale_factors, distribution,
+    filename_expansion_function=None):
   """Helper function that adds references to external images available in other
   scale_factors and removes images from image-sets in unsupported scale_factors.
   """
   # Explicitly add 1x to supported scale factors so that it is not removed.
   supported_scale_factors = ['1x']
   supported_scale_factors.extend(scale_factors)
-  return InsertImageSets(filepath,
-                         RemoveImageSetImages(text, supported_scale_factors),
-                         scale_factors,
-                         distribution)
+  return InsertImageSets(
+      filepath,
+      RemoveImageSetImages(text, supported_scale_factors),
+      scale_factors,
+      distribution,
+      filename_expansion_function=filename_expansion_function)
 
 
 class ChromeHtml(interface.GathererBase):
@@ -238,6 +255,7 @@ class ChromeHtml(interface.GathererBase):
     # 1x resources are implicitly already in the source and do not need to be
     # added.
     self.scale_factors_ = []
+    self.filename_expansion_function = None
 
   def SetAttributes(self, attrs):
     self.allow_external_script_ = ('allowexternalscript' in attrs and
@@ -267,7 +285,9 @@ class ChromeHtml(interface.GathererBase):
           self.grd_node.ToRealPath(self.GetInputPath()),
           allow_external_script=self.allow_external_script_,
           rewrite_function=lambda fp, t, d: ProcessImageSets(
-              fp, t, self.scale_factors_, d))
+              fp, t, self.scale_factors_, d,
+              filename_expansion_function=self.filename_expansion_function),
+          filename_expansion_function=self.filename_expansion_function)
     return []
 
   def Translate(self, lang, pseudo_if_not_available=True,
@@ -275,10 +295,15 @@ class ChromeHtml(interface.GathererBase):
     """Returns this document translated."""
     return self.inlined_text_
 
+  def SetFilenameExpansionFunction(self, fn):
+    self.filename_expansion_function = fn
+
   def Parse(self):
     """Parses and inlines the represented file."""
 
     filename = self.GetInputPath()
+    if self.filename_expansion_function:
+      filename = self.filename_expansion_function(filename)
     # Hack: some unit tests supply an absolute path and no root node.
     if not os.path.isabs(filename):
       filename = self.grd_node.ToRealPath(filename)
@@ -288,11 +313,14 @@ class ChromeHtml(interface.GathererBase):
           self.grd_node,
           allow_external_script = self.allow_external_script_,
           rewrite_function=lambda fp, t, d: ProcessImageSets(
-              fp, t, self.scale_factors_, d))
+              fp, t, self.scale_factors_, d,
+              filename_expansion_function=self.filename_expansion_function),
+          filename_expansion_function=self.filename_expansion_function)
     else:
       distribution = html_inline.GetDistribution()
       self.inlined_text_ = ProcessImageSets(
           os.path.dirname(filename),
           util.ReadFile(filename, 'utf-8'),
           self.scale_factors_,
-          distribution)
+          distribution,
+          filename_expansion_function=self.filename_expansion_function)
diff --git a/grit/gather/chrome_html_unittest.py b/grit/gather/chrome_html_unittest.py
index 7d0b702..8f636ff 100644
--- a/grit/gather/chrome_html_unittest.py
+++ b/grit/gather/chrome_html_unittest.py
@@ -345,5 +345,62 @@ class ChromeHtmlUnittest(unittest.TestCase):
       '''))
     tmp_dir.CleanUp()
 
+  def testExpandVariablesInFilename(self):
+    '''
+    Tests variable substitution in filenames while flattening images
+    with multiple scale factors.
+    '''
+
+    tmp_dir = util.TempDir({
+      'index.html': '''
+      <!DOCTYPE HTML>
+      <html>
+        <head>
+          <link rel="stylesheet" href="test.css">
+        </head>
+        <body>
+          <!-- Don't need a body. -->
+        </body>
+      </html>
+      ''',
+
+      'test.css': '''
+      .image {
+        background: url('test[WHICH].png');
+      }
+      ''',
+
+      'test1.png': 'PNG DATA',
+      '1.4x/test1.png': '1.4x PNG DATA',
+      '1.8x/test1.png': '1.8x PNG DATA',
+    })
+
+    def replacer(var, repl):
+      return lambda filename: filename.replace('[%s]' % var, repl)
+
+    html = chrome_html.ChromeHtml(tmp_dir.GetPath('index.html'))
+    html.SetDefines({'scale_factors': '1.4x,1.8x'})
+    html.SetAttributes({'flattenhtml': 'true'})
+    html.SetFilenameExpansionFunction(replacer('WHICH', '1'));
+    html.Parse()
+    self.failUnlessEqual(StandardizeHtml(html.GetData('en', 'utf-8')),
+                         StandardizeHtml('''
+      <!DOCTYPE HTML>
+      <html>
+        <head>
+          <style>
+      .image {
+        background: -webkit-image-set(url('data:image/png;base64,UE5HIERBVEE=') 1x, url('data:image/png;base64,MS40eCBQTkcgREFUQQ==') 1.4x, url('data:image/png;base64,MS44eCBQTkcgREFUQQ==') 1.8x);
+      }
+      </style>
+        </head>
+        <body>
+          <!-- Don't need a body. -->
+        </body>
+      </html>
+      '''))
+    tmp_dir.CleanUp()
+
+
 if __name__ == '__main__':
   unittest.main()
diff --git a/grit/gather/interface.py b/grit/gather/interface.py
index 084392a..c277d37 100644
--- a/grit/gather/interface.py
+++ b/grit/gather/interface.py
@@ -152,6 +152,10 @@ class GathererBase(object):
     '''
     pass
 
+  def SetFilenameExpansionFunction(self, fn):
+    '''Sets a function for rewriting filenames before gathering.'''
+    pass
+
   # TODO(benrg): Move this elsewhere, since it isn't part of the interface.
   def _LoadInputFile(self):
     '''A convenience function for subclasses that loads the contents of the
diff --git a/grit/node/structure.py b/grit/node/structure.py
index 99f2014..48968f6 100644
--- a/grit/node/structure.py
+++ b/grit/node/structure.py
@@ -93,6 +93,8 @@ class StructureNode(base.Node):
     if hasattr(self.GetRoot(), 'defines'):
       self.gatherer.SetDefines(self.GetRoot().defines)
     self.gatherer.SetAttributes(self.attrs)
+    if self.ExpandVariables():
+      self.gatherer.SetFilenameExpansionFunction(self._Substitute)
 
     # Parse local variables and instantiate the substituter.
     if self.attrs['variables']:
@@ -109,6 +111,10 @@ class StructureNode(base.Node):
                         is_skeleton=True)
       skel.SetGrdNode(self)  # TODO(benrg): Or child? Only used for ToRealPath
       skel.SetUberClique(self.UberClique())
+      if hasattr(self.GetRoot(), 'defines'):
+        skel.SetDefines(self.GetRoot().defines)
+      if self.ExpandVariables():
+        skel.SetFilenameExpansionFunction(self._Substitute)
       self.skeletons[child.attrs['expr']] = skel
 
   def MandatoryAttributes(self):
diff --git a/grit/node/structure_unittest.py b/grit/node/structure_unittest.py
index c07c2bc..a039bce 100644
--- a/grit/node/structure_unittest.py
+++ b/grit/node/structure_unittest.py
@@ -49,7 +49,7 @@ class StructureUnittest(unittest.TestCase):
   def testVariables(self):
     grd = util.ParseGrdForUnittest('''
         <structures>
-          <structure type="chrome_html" name="hello_tmpl" file="structure_variables.html" expand_variables="true" variables="GREETING=Hello,THINGS=foo,, bar,, baz,EQUATION=2+2==4"></structure>
+          <structure type="chrome_html" name="hello_tmpl" file="structure_variables.html" expand_variables="true" variables="GREETING=Hello,THINGS=foo,, bar,, baz,EQUATION=2+2==4,filename=simple" flattenhtml="true"></structure>
         </structures>''', base_dir=util.PathFromRoot('grit/testdata'))
     grd.SetOutputLanguage('en')
     grd.RunGatherers()
@@ -57,9 +57,12 @@ class StructureUnittest(unittest.TestCase):
     filename = node.Process(tempfile.gettempdir())
     with open(os.path.join(tempfile.gettempdir(), filename)) as f:
       result = f.read()
-      self.failUnless(result == ('<h1>Hello!</h1>\n'
-                                 'Some cool things are foo, bar, baz.\n'
-                                 'Did you know that 2+2==4?\n'))
+      self.failUnlessEqual(('<h1>Hello!</h1>\n'
+                            'Some cool things are foo, bar, baz.\n'
+                            'Did you know that 2+2==4?\n'
+                            '<p>\n'
+                            '  Hello!\n'
+                            '</p>\n'), result)
 
 
 if __name__ == '__main__':
diff --git a/grit/testdata/structure_variables.html b/grit/testdata/structure_variables.html
index c90bfc9..2a15de8 100644
--- a/grit/testdata/structure_variables.html
+++ b/grit/testdata/structure_variables.html
@@ -1,3 +1,4 @@
 <h1>[GREETING]!</h1>
 Some cool things are [THINGS].
 Did you know that [EQUATION]?
+<include src="[filename].html">