Auto merge of #9272 - Ms2ger:dpi, r=ato

Support device-pixel-ratio in wpt reftests.

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16 files changed, 134 insertions, 22 deletions

diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index 60c869a4d84..4ee563b6c09 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -4,8 +4,5 @@
 # Should be == with expected failure:
 fragment=top != ../html/acid2.html acid2_ref.html
 
-resolution=300x300,device-pixel-ratio=2 != pixel_snapping_border_a.html pixel_snapping_border_ref.html
-resolution=300x300,device-pixel-ratio=2 != pixel_snapping_position_a.html pixel_snapping_position_ref.html
-
 # This file must be sorted alphabetically.
 # Please run `./mach test-tidy` to check your changes.
diff --git a/tests/wpt/css-tests/tools/manifest/item.py b/tests/wpt/css-tests/tools/manifest/item.py
index 8ee17004495..70f51d10cb9 100644
--- a/tests/wpt/css-tests/tools/manifest/item.py
+++ b/tests/wpt/css-tests/tools/manifest/item.py
@@ -123,7 +123,7 @@ class RefTest(URLManifestItem):
     item_type = "reftest"
 
     def __init__(self, source_file, url, references, url_base="/", timeout=None,
-                 viewport_size=None, manifest=None):
+                 viewport_size=None, dpi=None, manifest=None):
         URLManifestItem.__init__(self, source_file, url, url_base=url_base, manifest=manifest)
         for _, ref_type in references:
             if ref_type not in ["==", "!="]:
@@ -131,13 +131,14 @@ class RefTest(URLManifestItem):
         self.references = tuple(references)
         self.timeout = timeout
         self.viewport_size = viewport_size
+        self.dpi = dpi
 
     @property
     def is_reference(self):
         return self.source_file.name_is_reference
 
     def meta_key(self):
-        return (self.timeout, self.viewport_size)
+        return (self.timeout, self.viewport_size, self.dpi)
 
     def to_json(self):
         rv = URLManifestItem.to_json(self)
@@ -146,6 +147,8 @@ class RefTest(URLManifestItem):
             rv["timeout"] = self.timeout
         if self.viewport_size is not None:
             rv["viewport_size"] = self.viewport_size
+        if self.dpi is not None:
+            rv["dpi"] = self.dpi
         return rv
 
     @classmethod
@@ -157,6 +160,7 @@ class RefTest(URLManifestItem):
                    url_base=manifest.url_base,
                    timeout=obj.get("timeout"),
                    viewport_size=obj.get("viewport_size"),
+                   dpi=obj.get("dpi"),
                    manifest=manifest)
 
 
diff --git a/tests/wpt/css-tests/tools/manifest/sourcefile.py b/tests/wpt/css-tests/tools/manifest/sourcefile.py
index 3681f85276e..fb592272119 100644
--- a/tests/wpt/css-tests/tools/manifest/sourcefile.py
+++ b/tests/wpt/css-tests/tools/manifest/sourcefile.py
@@ -198,6 +198,23 @@ class SourceFile(object):
         return self.viewport_nodes[0].attrib.get("content", None)
 
     @cached_property
+    def dpi_nodes(self):
+        """List of ElementTree Elements corresponding to nodes in a test that
+        specify device pixel ratios"""
+        return self.root.findall(".//{http://www.w3.org/1999/xhtml}meta[@name='device-pixel-ratio']")
+
+    @cached_property
+    def dpi(self):
+        """The device pixel ratio of a test or reference file"""
+        if not self.root:
+            return None
+
+        if not self.dpi_nodes:
+            return None
+
+        return self.dpi_nodes[0].attrib.get("content", None)
+
+    @cached_property
     def testharness_nodes(self):
         """List of ElementTree Elements corresponding to nodes representing a
         testharness.js script"""
@@ -288,7 +305,8 @@ class SourceFile(object):
                 rv.append(TestharnessTest(self, url, timeout=self.timeout))
 
         elif self.content_is_ref_node:
-            rv = [RefTest(self, self.url, self.references, timeout=self.timeout, viewport_size=self.viewport_size)]
+            rv = [RefTest(self, self.url, self.references, timeout=self.timeout,
+                          viewport_size=self.viewport_size, dpi=self.dpi)]
 
         else:
             # If nothing else it's a helper file, which we don't have a specific type for
diff --git a/tests/wpt/harness/wptrunner/executors/base.py b/tests/wpt/harness/wptrunner/executors/base.py
index 614eeee86e6..0c8c2a1bc50 100644
--- a/tests/wpt/harness/wptrunner/executors/base.py
+++ b/tests/wpt/harness/wptrunner/executors/base.py
@@ -206,12 +206,12 @@ class RefTestImplementation(object):
     def logger(self):
         return self.executor.logger
 
-    def get_hash(self, test, viewport_size):
+    def get_hash(self, test, viewport_size, dpi):
         timeout = test.timeout * self.timeout_multiplier
-        key = (test.url, viewport_size)
+        key = (test.url, viewport_size, dpi)
 
         if key not in self.screenshot_cache:
-            success, data = self.executor.screenshot(test, viewport_size)
+            success, data = self.executor.screenshot(test, viewport_size, dpi)
 
             if not success:
                 return False, data
@@ -236,6 +236,7 @@ class RefTestImplementation(object):
 
     def run_test(self, test):
         viewport_size = test.viewport_size
+        dpi = test.dpi
         self.message = []
 
         # Depth-first search of reference tree, with the goal
@@ -249,7 +250,7 @@ class RefTestImplementation(object):
             nodes, relation = stack.pop()
 
             for i, node in enumerate(nodes):
-                success, data = self.get_hash(node, viewport_size)
+                success, data = self.get_hash(node, viewport_size, dpi)
                 if success is False:
                     return {"status": data[0], "message": data[1]}
 
@@ -266,7 +267,7 @@ class RefTestImplementation(object):
 
         for i, (node, screenshot) in enumerate(zip(nodes, screenshots)):
             if screenshot is None:
-                success, screenshot = self.retake_screenshot(node, viewport_size)
+                success, screenshot = self.retake_screenshot(node, viewport_size, dpi)
                 if success:
                     screenshots[i] = screenshot
 
@@ -277,12 +278,12 @@ class RefTestImplementation(object):
                 "message": "\n".join(self.message),
                 "extra": {"reftest_screenshots": log_data}}
 
-    def retake_screenshot(self, node, viewport_size):
-        success, data = self.executor.screenshot(node, viewport_size)
+    def retake_screenshot(self, node, viewport_size, dpi):
+        success, data = self.executor.screenshot(node, viewport_size, dpi)
         if not success:
             return False, data
 
-        key = (node.url, viewport_size)
+        key = (node.url, viewport_size, dpi)
         hash_val, _ = self.screenshot_cache[key]
         self.screenshot_cache[key] = hash_val, data
         return True, data
diff --git a/tests/wpt/harness/wptrunner/executors/executormarionette.py b/tests/wpt/harness/wptrunner/executors/executormarionette.py
index ecae5ac5e77..c502b425da2 100644
--- a/tests/wpt/harness/wptrunner/executors/executormarionette.py
+++ b/tests/wpt/harness/wptrunner/executors/executormarionette.py
@@ -385,9 +385,10 @@ class MarionetteRefTestExecutor(RefTestExecutor):
 
         return self.convert_result(test, result)
 
-    def screenshot(self, test, viewport_size):
+    def screenshot(self, test, viewport_size, dpi):
         # https://github.com/w3c/wptrunner/issues/166
         assert viewport_size is None
+        assert dpi is None
 
         timeout =  self.timeout_multiplier * test.timeout if self.debug_info is None else None
 
diff --git a/tests/wpt/harness/wptrunner/executors/executorselenium.py b/tests/wpt/harness/wptrunner/executors/executorselenium.py
index 5671d476f57..587c49c7c92 100644
--- a/tests/wpt/harness/wptrunner/executors/executorselenium.py
+++ b/tests/wpt/harness/wptrunner/executors/executorselenium.py
@@ -247,9 +247,10 @@ class SeleniumRefTestExecutor(RefTestExecutor):
 
         return self.convert_result(test, result)
 
-    def screenshot(self, test, viewport_size):
+    def screenshot(self, test, viewport_size, dpi):
         # https://github.com/w3c/wptrunner/issues/166
         assert viewport_size is None
+        assert dpi is None
 
         return SeleniumRun(self._screenshot,
                            self.protocol.webdriver,
diff --git a/tests/wpt/harness/wptrunner/executors/executorservo.py b/tests/wpt/harness/wptrunner/executors/executorservo.py
index 0f25aaf7b71..8189e9ac7b8 100644
--- a/tests/wpt/harness/wptrunner/executors/executorservo.py
+++ b/tests/wpt/harness/wptrunner/executors/executorservo.py
@@ -196,7 +196,7 @@ class ServoRefTestExecutor(ProcessTestExecutor):
         os.rmdir(self.tempdir)
         ProcessTestExecutor.teardown(self)
 
-    def screenshot(self, test, viewport_size):
+    def screenshot(self, test, viewport_size, dpi):
         full_url = self.test_url(test)
 
         with TempFilename(self.tempdir) as output_path:
@@ -216,6 +216,9 @@ class ServoRefTestExecutor(ProcessTestExecutor):
             if viewport_size:
                 command += ["--resolution", viewport_size]
 
+            if dpi:
+                command += ["--device-pixel-ratio", dpi]
+
             self.command = debug_args + command
 
             env = os.environ.copy()
diff --git a/tests/wpt/harness/wptrunner/executors/executorservodriver.py b/tests/wpt/harness/wptrunner/executors/executorservodriver.py
index 0317ca61cb8..52154d09ba0 100644
--- a/tests/wpt/harness/wptrunner/executors/executorservodriver.py
+++ b/tests/wpt/harness/wptrunner/executors/executorservodriver.py
@@ -226,9 +226,10 @@ class ServoWebDriverRefTestExecutor(RefTestExecutor):
             message += traceback.format_exc(e)
             return test.result_cls("ERROR", message), []
 
-    def screenshot(self, test, viewport_size):
+    def screenshot(self, test, viewport_size, dpi):
         # https://github.com/w3c/wptrunner/issues/166
         assert viewport_size is None
+        assert dpi is None
 
         timeout = (test.timeout * self.timeout_multiplier + extra_timeout
                    if self.debug_info is None else None)
diff --git a/tests/wpt/harness/wptrunner/wpttest.py b/tests/wpt/harness/wptrunner/wpttest.py
index 82bcc689b6b..73a50bb129e 100644
--- a/tests/wpt/harness/wptrunner/wpttest.py
+++ b/tests/wpt/harness/wptrunner/wpttest.py
@@ -216,7 +216,7 @@ class ReftestTest(Test):
 
     def __init__(self, url, inherit_metadata, test_metadata, references,
                  timeout=DEFAULT_TIMEOUT, path=None, viewport_size=None,
-                 protocol="http"):
+                 dpi=None, protocol="http"):
         Test.__init__(self, url, inherit_metadata, test_metadata, timeout, path, protocol)
 
         for _, ref_type in references:
@@ -225,6 +225,7 @@ class ReftestTest(Test):
 
         self.references = references
         self.viewport_size = viewport_size
+        self.dpi = dpi
 
     @classmethod
     def from_manifest(cls,
@@ -250,6 +251,7 @@ class ReftestTest(Test):
                    timeout=timeout,
                    path=manifest_test.path,
                    viewport_size=manifest_test.viewport_size,
+                   dpi=manifest_test.dpi,
                    protocol="https" if hasattr(manifest_test, "https") and manifest_test.https else "http")
 
         nodes[url] = node
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 83dbc474127..d6fc30b6a8f 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -3511,6 +3511,34 @@
             "url": "/_mozilla/css/percentage_width_inline_block_a.html"
           }
         ],
+        "css/pixel_snapping_border_a.html": [
+          {
+            "dpi": "2",
+            "path": "css/pixel_snapping_border_a.html",
+            "references": [
+              [
+                "/_mozilla/css/pixel_snapping_border_ref.html",
+                "!="
+              ]
+            ],
+            "url": "/_mozilla/css/pixel_snapping_border_a.html",
+            "viewport_size": "300x300"
+          }
+        ],
+        "css/pixel_snapping_position_a.html": [
+          {
+            "dpi": "2",
+            "path": "css/pixel_snapping_position_a.html",
+            "references": [
+              [
+                "/_mozilla/css/pixel_snapping_position_ref.html",
+                "!="
+              ]
+            ],
+            "url": "/_mozilla/css/pixel_snapping_position_a.html",
+            "viewport_size": "300x300"
+          }
+        ],
         "css/png_rgba_colorspace_a.html": [
           {
             "path": "css/png_rgba_colorspace_a.html",
@@ -9526,6 +9554,34 @@
           "url": "/_mozilla/css/percentage_width_inline_block_a.html"
         }
       ],
+      "css/pixel_snapping_border_a.html": [
+        {
+          "dpi": "2",
+          "path": "css/pixel_snapping_border_a.html",
+          "references": [
+            [
+              "/_mozilla/css/pixel_snapping_border_ref.html",
+              "!="
+            ]
+          ],
+          "url": "/_mozilla/css/pixel_snapping_border_a.html",
+          "viewport_size": "300x300"
+        }
+      ],
+      "css/pixel_snapping_position_a.html": [
+        {
+          "dpi": "2",
+          "path": "css/pixel_snapping_position_a.html",
+          "references": [
+            [
+              "/_mozilla/css/pixel_snapping_position_ref.html",
+              "!="
+            ]
+          ],
+          "url": "/_mozilla/css/pixel_snapping_position_a.html",
+          "viewport_size": "300x300"
+        }
+      ],
       "css/png_rgba_colorspace_a.html": [
         {
           "path": "css/png_rgba_colorspace_a.html",
diff --git a/tests/ref/pixel_snapping_border_a.html b/tests/wpt/mozilla/tests/css/pixel_snapping_border_a.html
index 78d76b1b353..c55be8adeb7 100644
--- a/tests/ref/pixel_snapping_border_a.html
+++ b/tests/wpt/mozilla/tests/css/pixel_snapping_border_a.html
@@ -3,6 +3,9 @@
   <head>
     <meta charset="UTF-8">
     <title>Pixel snapping border test</title>
+    <meta name=device-pixel-ratio content=2>
+    <meta name=viewport-size content=300x300>
+    <link rel=mismatch href=pixel_snapping_border_ref.html>
     <style>
       div {
         height: 101px;
diff --git a/tests/ref/pixel_snapping_border_ref.html b/tests/wpt/mozilla/tests/css/pixel_snapping_border_ref.html
index 483046f65cf..483046f65cf 100644
--- a/tests/ref/pixel_snapping_border_ref.html
+++ b/tests/wpt/mozilla/tests/css/pixel_snapping_border_ref.html
diff --git a/tests/ref/pixel_snapping_position_a.html b/tests/wpt/mozilla/tests/css/pixel_snapping_position_a.html
index a62dd36bbb4..ed438f9ed50 100644
--- a/tests/ref/pixel_snapping_position_a.html
+++ b/tests/wpt/mozilla/tests/css/pixel_snapping_position_a.html
@@ -3,6 +3,9 @@
   <head>
     <meta charset="UTF-8">
     <title>Pixel snapping position test</title>
+    <meta name=device-pixel-ratio content=2>
+    <meta name=viewport-size content=300x300>
+    <link rel=mismatch href=pixel_snapping_position_ref.html>
     <style>
       div {
         position: absolute;
diff --git a/tests/ref/pixel_snapping_position_ref.html b/tests/wpt/mozilla/tests/css/pixel_snapping_position_ref.html
index 58e3e4eddb0..58e3e4eddb0 100644
--- a/tests/ref/pixel_snapping_position_ref.html
+++ b/tests/wpt/mozilla/tests/css/pixel_snapping_position_ref.html
diff --git a/tests/wpt/web-platform-tests/tools/manifest/item.py b/tests/wpt/web-platform-tests/tools/manifest/item.py
index f03ea9d61b5..55bbbe80a5a 100644
--- a/tests/wpt/web-platform-tests/tools/manifest/item.py
+++ b/tests/wpt/web-platform-tests/tools/manifest/item.py
@@ -130,7 +130,7 @@ class RefTest(URLManifestItem):
     item_type = "reftest"
 
     def __init__(self, source_file, url, references, url_base="/", timeout=None,
-                 viewport_size=None, manifest=None):
+                 viewport_size=None, dpi=None, manifest=None):
         URLManifestItem.__init__(self, source_file, url, url_base=url_base, manifest=manifest)
         for _, ref_type in references:
             if ref_type not in ["==", "!="]:
@@ -138,13 +138,14 @@ class RefTest(URLManifestItem):
         self.references = tuple(references)
         self.timeout = timeout
         self.viewport_size = viewport_size
+        self.dpi = dpi
 
     @property
     def is_reference(self):
         return self.source_file.name_is_reference
 
     def meta_key(self):
-        return (self.timeout, self.viewport_size)
+        return (self.timeout, self.viewport_size, self.dpi)
 
     def to_json(self):
         rv = URLManifestItem.to_json(self)
@@ -153,6 +154,8 @@ class RefTest(URLManifestItem):
             rv["timeout"] = self.timeout
         if self.viewport_size is not None:
             rv["viewport_size"] = self.viewport_size
+        if self.dpi is not None:
+            rv["dpi"] = self.dpi
         return rv
 
     @classmethod
@@ -165,6 +168,7 @@ class RefTest(URLManifestItem):
                    url_base=manifest.url_base,
                    timeout=obj.get("timeout"),
                    viewport_size=obj.get("viewport_size"),
+                   dpi=obj.get("dpi"),
                    manifest=manifest)
 
 
diff --git a/tests/wpt/web-platform-tests/tools/manifest/sourcefile.py b/tests/wpt/web-platform-tests/tools/manifest/sourcefile.py
index 8950e7b1fbc..14cbdd780ca 100644
--- a/tests/wpt/web-platform-tests/tools/manifest/sourcefile.py
+++ b/tests/wpt/web-platform-tests/tools/manifest/sourcefile.py
@@ -198,6 +198,23 @@ class SourceFile(object):
         return self.viewport_nodes[0].attrib.get("content", None)
 
     @cached_property
+    def dpi_nodes(self):
+        """List of ElementTree Elements corresponding to nodes in a test that
+        specify device pixel ratios"""
+        return self.root.findall(".//{http://www.w3.org/1999/xhtml}meta[@name='device-pixel-ratio']")
+
+    @cached_property
+    def dpi(self):
+        """The device pixel ratio of a test or reference file"""
+        if not self.root:
+            return None
+
+        if not self.dpi_nodes:
+            return None
+
+        return self.dpi_nodes[0].attrib.get("content", None)
+
+    @cached_property
     def testharness_nodes(self):
         """List of ElementTree Elements corresponding to nodes representing a
         testharness.js script"""
@@ -288,7 +305,8 @@ class SourceFile(object):
                 rv.append(TestharnessTest(self, url, timeout=self.timeout))
 
         elif self.content_is_ref_node:
-            rv = [RefTest(self, self.url, self.references, timeout=self.timeout, viewport_size=self.viewport_size)]
+            rv = [RefTest(self, self.url, self.references, timeout=self.timeout,
+                          viewport_size=self.viewport_size, dpi=self.dpi)]
 
         else:
             # If nothing else it's a helper file, which we don't have a specific type for