WebUI: Add preserve_url_scheme option in polymer_modulizer()

In some cases, like the FilesApp which is served from a
chrome-extension:// scheme, converting all chrome:// URLs to
scheme-relative URLs is not desired.

Adding a |preserve_url_scheme| to opt-out of the default behavior.

Bug: 1128313
Change-Id: I48fe8fda4320d8ff3eaca35229c8c34cd55407de
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2411563Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: dpapad <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#807369}

tools/polymer/polymer.gni

@@ -71,5 +71,9 @@ template("polymer_modulizer") {
     if (defined(invoker.migrated_imports)) {
       args += [ "--migrated_imports" ] + invoker.migrated_imports
     }
+
+    if (defined(invoker.preserve_url_scheme) && invoker.preserve_url_scheme) {
+      args += [ "--preserve_url_scheme" ]
+    }
   }
 }

tools/polymer/polymer.py

@@ -79,6 +79,11 @@ _ignore_imports = []
 
 _migrated_imports = []
 
+# Populated from command line arguments. Specifies whether "chrome://" URLs
+# should be preserved, or whether they should be converted to scheme-relative
+# URLs "//" (default behavior).
+_preserve_url_scheme = False
+
 # Use an OrderedDict, since the order these redirects are applied matters.
 _chrome_redirects = OrderedDict([
     ('chrome://resources/polymer/v1_0/', POLYMER_V1_DIR),
@@ -97,18 +102,23 @@ _chrome_reverse_redirects = {
 # imports. |to_js_import()| is the only public method exposed by this class.
 # Internally an HTML import path is
 #
-# 1) normalized, meaning converted from a chrome or relative URL to to an
-#    absolute path starting at the repo's root
+# 1) normalized, meaning converted from a chrome or scheme-relative or relative
+#    URL to to an absolute path starting at the repo's root
 # 2) converted to an equivalent JS normalized path
-# 3) de-normalized, meaning converted back to a relative or chrome URL
+# 3) de-normalized, meaning converted back to a chrome or scheme-relative or
+#    relative URL
 # 4) converted to a JS import statement
 class Dependency:
   def __init__(self, src, dst):
     self.html_file = src
     self.html_path = dst
 
-    self.input_format = ('chrome' if self.html_path.startswith('chrome://')
-                         or self.html_path.startswith('//') else 'relative')
+    if self.html_path.startswith('chrome://'):
+      self.input_format = 'chrome'
+    elif self.html_path.startswith('//'):
+      self.input_format = 'scheme-relative'
+    else:
+      self.input_format = 'relative'
     self.output_format = self.input_format
 
     self.html_path_normalized = self._to_html_normalized()
@@ -116,7 +126,7 @@ class Dependency:
     self.js_path = self._to_js()
 
   def _to_html_normalized(self):
-    if self.input_format == 'chrome':
+    if self.input_format == 'chrome' or self.input_format == 'scheme-relative':
       self.html_path_normalized = self.html_path
       for r in _chrome_redirects:
         if self.html_path.startswith(r):
@@ -136,7 +146,8 @@ class Dependency:
           .replace(r'.html', '.js'))
 
     if self.html_path_normalized == 'ui/webui/resources/html/polymer.html':
-      self.output_format = 'chrome'
+      if self.output_format == 'relative':
+        self.output_format = 'chrome'
       return POLYMER_V3_DIR + 'polymer/polymer_bundled.min.js'
 
     if re.match(r'ui/webui/resources/html/', self.html_path_normalized):
@@ -151,14 +162,19 @@ class Dependency:
   def _to_js(self):
     js_path = self.js_path_normalized
 
-    if self.output_format == 'chrome':
+    if self.output_format == 'chrome' or self.output_format == 'scheme-relative':
       for r in _chrome_reverse_redirects:
         if self.js_path_normalized.startswith(r):
           js_path = self.js_path_normalized.replace(
               r, _chrome_reverse_redirects[r])
           break
+
+      # Restore the chrome:// scheme if |preserve_url_scheme| is enabled.
+      if _preserve_url_scheme and self.output_format == 'chrome':
+        js_path = "chrome:" + js_path
       return js_path
 
+    assert self.output_format == 'relative'
     input_dir = os.path.relpath(os.path.dirname(self.html_file), _ROOT)
     relpath = os.path.relpath(
         self.js_path_normalized, input_dir).replace("\\", "/")
@@ -512,6 +528,7 @@ def main(argv):
   parser.add_argument('--ignore_imports', required=False, nargs="*")
   parser.add_argument('--auto_imports', required=False, nargs="*")
   parser.add_argument('--migrated_imports', required=False, nargs="*")
+  parser.add_argument('--preserve_url_scheme', action="store_true")
   parser.add_argument(
       '--html_type', choices=['dom-module', 'style-module', 'custom-style',
       'iron-iconset', 'v3-ready'],
@@ -543,6 +560,10 @@ def main(argv):
     global _migrated_imports
     _migrated_imports = args.migrated_imports
 
+  # Extract |preserve_url_scheme| from arguments.
+  global _preserve_url_scheme
+  _preserve_url_scheme = args.preserve_url_scheme
+
   in_folder = os.path.normpath(os.path.join(_CWD, args.in_folder))
   out_folder = os.path.normpath(os.path.join(_CWD, args.out_folder))
 

tools/polymer/polymer_test.py

@@ -165,54 +165,79 @@ class PolymerModulizerTest(unittest.TestCase):
         # Case where relative path to polymer.html is used.
         [
             '../../html/polymer.html',
-            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';'
+            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
+            'import {Polymer, html} from \'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
         ],
         # Case where relative path to file in the same folder is used.
-        ['foo.html', 'import \'./foo.m.js\';'],
+        [
+            'foo.html',
+            'import \'./foo.m.js\';',
+            'import \'./foo.m.js\';',
+        ],
         # Case where relative path to file in the same subtree is used.
         [
             'path/to/subfolder/foo.html',
-            'import \'./path/to/subfolder/foo.m.js\';'
+            'import \'./path/to/subfolder/foo.m.js\';',
+            'import \'./path/to/subfolder/foo.m.js\';',
         ],
         # Case where relative path to file in ui/webui/resources/html/ is used.
-        ['../../html/foo.html', 'import {Foo} from \'../../js/foo.m.js\';'],
+        [
+            '../../html/foo.html',
+            'import {Foo} from \'../../js/foo.m.js\';',
+            'import {Foo} from \'../../js/foo.m.js\';',
+        ],
 
         # chrome:// paths cases.
         # Case where absolute path to a Polymer UI element is used.
         [
             'chrome://resources/polymer/v1_0/path/to/folder/foo.html',
-            'import \'//resources/polymer/v3_0/path/to/folder/foo.js\';'
+            'import \'//resources/polymer/v3_0/path/to/folder/foo.js\';',
+            'import \'chrome://resources/polymer/v3_0/path/to/folder/foo.js\';',
         ],
         # Case where chrome:// path to polymer.html is used.
         [
             'chrome://resources/html/polymer.html',
-            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';'
+            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
+            'import {Polymer, html} from \'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
         ],
         # Case where chrome://resources/html/ path to something other than
         # polymer.html is used.
         [
             'chrome://resources/html/bar.html',
-            'import \'//resources/js/bar.m.js\';'
+            'import \'//resources/js/bar.m.js\';',
+            'import \'chrome://resources/js/bar.m.js\';',
         ],
 
         # Scheme-relative paths cases.
         # Case where absolute path to a Polymer UI element is used.
         [
             '//resources/polymer/v1_0/path/to/folder/foo.html',
-            'import \'//resources/polymer/v3_0/path/to/folder/foo.js\';'
+            'import \'//resources/polymer/v3_0/path/to/folder/foo.js\';',
+            'import \'//resources/polymer/v3_0/path/to/folder/foo.js\';',
         ],
         # Case where path to polymer.html is used.
         [
             '//resources/html/polymer.html',
-            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';'
+            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
+            'import {Polymer, html} from \'//resources/polymer/v3_0/polymer/polymer_bundled.min.js\';',
         ],
         # Case where //resources/html/ path to something other than
         # polymer.html is used.
-        ['//resources/html/bar.html', 'import \'//resources/js/bar.m.js\';'],
+        [
+            '//resources/html/bar.html',
+            'import \'//resources/js/bar.m.js\';',
+            'import \'//resources/js/bar.m.js\';',
+        ],
     ]
 
-    for [html, js_expected] in cases:
-      assert_html_to_js(html, js_expected)
+    for [html, js_expected1, js_expected2] in cases:
+      # Test case where |preserve_url_scheme| is False
+      polymer._preserve_url_scheme = False
+      assert_html_to_js(html, js_expected1)
+
+      # Test case where |preserve_url_scheme| is True
+      polymer._preserve_url_scheme = True
+      assert_html_to_js(html, js_expected2)
 
 
 if __name__ == '__main__':