Make the macOS display configuration also change display mode

This renames the `macos-color-profile` command to
`macos-display-configuration` (as it is a CI command, it is reasonable
to believe this is safe), and expands its scope.

Along with color space, we now also attempt to make the smallest
change possible to the display mode such that we end up on a 1x
display mode.

Author: gsnedders

.github/workflows/safari-wptrunner.yml

@@ -68,9 +68,9 @@ jobs:
           REV: ${{ inputs.test-rev }}
         run: |-
           git switch --force --progress -d "$REV"
-      - name: Set display color profile
+      - name: Reconfigure the display(s)
         run: |-
-          ./wpt macos-color-profile
+          ./wpt macos-display-configuration
       - name: Set system caption style to ""
         run: |-
           defaults write com.apple.mediaaccessibility MACaptionActiveProfile -string ""

tools/ci/azure/color_profile.yml

@@ -1,5 +1,5 @@
 steps:
 - script: |
-    ./wpt macos-color-profile
-  displayName: 'Set display color profile'
+    ./wpt macos-display-configuration
+  displayName: 'Reconfigure the display(s)'
   condition: and(succeeded(), eq(variables['Agent.OS'], 'Darwin'))

tools/ci/commands.json

@@ -13,13 +13,14 @@
     "help": "Output a hosts file to stdout",
     "virtualenv": false
   },
-  "macos-color-profile": {
-    "path": "macos_color_profile.py",
+  "macos-display-configuration": {
+    "path": "macos_display_configuration.py",
     "script": "run",
-    "help": "Change the macOS color profile to sRGB",
+    "parser": "create_parser",
+    "help": "Configure macOS displays (scale, color profile)",
     "virtualenv": true,
     "requirements": [
-      "requirements_macos_color_profile.txt"
+      "requirements_macos_display_configuration.txt"
     ]
   },
   "regen-certs": {

tools/ci/macos_color_profile.py

@@ -0,0 +1,239 @@
+import argparse
+import sys
+from typing import Any, NewType, Optional, Tuple
+
+from Cocoa import NSURL
+from ColorSync import (
+    CGDisplayCreateUUIDFromDisplayID,
+    ColorSyncDeviceSetCustomProfiles,
+    kColorSyncDeviceDefaultProfileID,
+    kColorSyncDisplayDeviceClass,
+)
+from Quartz import (
+    CGBeginDisplayConfiguration,
+    CGCancelDisplayConfiguration,
+    CGCompleteDisplayConfiguration,
+    CGConfigureDisplayWithDisplayMode,
+    CGDisplayCopyAllDisplayModes,
+    CGDisplayCopyDisplayMode,
+    CGDisplayModeGetHeight,
+    CGDisplayModeGetIOFlags,
+    CGDisplayModeGetPixelHeight,
+    CGDisplayModeGetPixelWidth,
+    CGDisplayModeGetRefreshRate,
+    CGDisplayModeGetWidth,
+    CGDisplayModeIsUsableForDesktopGUI,
+    CGDisplayModeRef,
+    CGGetOnlineDisplayList,
+    kCGConfigurePermanently,
+    kCGErrorSuccess,
+)
+
+# Display mode flags
+kDisplayModeDefaultFlag = 0x00000004  # noqa: N816
+
+# Create a new type for display IDs
+CGDirectDisplayID = NewType("CGDirectDisplayID", int)
+
+
+def get_pixel_size(mode: CGDisplayModeRef) -> Tuple[int, int]:
+    return (CGDisplayModeGetPixelWidth(mode), CGDisplayModeGetPixelHeight(mode))
+
+
+def get_size(mode: CGDisplayModeRef) -> Tuple[int, int]:
+    return (CGDisplayModeGetWidth(mode), CGDisplayModeGetHeight(mode))
+
+
+def calculate_mode_similarity_score(
+    mode: CGDisplayModeRef, current_mode: CGDisplayModeRef
+) -> int:
+    current_size = get_size(current_mode)
+    current_pixel_size = get_pixel_size(current_mode)
+    current_refresh_rate = CGDisplayModeGetRefreshRate(current_mode)
+    current_flags = CGDisplayModeGetIOFlags(current_mode)
+
+    size = get_size(mode)
+    pixel_size = get_pixel_size(mode)
+    refresh_rate = CGDisplayModeGetRefreshRate(mode)
+    flags = CGDisplayModeGetIOFlags(mode)
+
+    differences = 0
+
+    if size != current_size:
+        differences += 1
+    if pixel_size != current_pixel_size:
+        differences += 1
+    if refresh_rate != current_refresh_rate:
+        differences += 1
+
+    # Count how many individual flags are changing (XOR then count bits)
+    changed_flags = flags ^ current_flags
+    if sys.version_info >= (3, 10):
+        differences += changed_flags.bit_count()
+    else:
+        differences += bin(changed_flags).count("1")
+
+    return differences
+
+
+def find_best_unscaled_mode(display_id: CGDirectDisplayID) -> CGDisplayModeRef:
+    current_mode: Optional[CGDisplayModeRef] = CGDisplayCopyDisplayMode(display_id)
+
+    # If we already have an unscaled mode, we're done.
+    if current_mode and (
+        get_size(current_mode) == get_pixel_size(current_mode)
+    ):
+        return current_mode
+
+    all_modes = CGDisplayCopyAllDisplayModes(display_id, None)
+    if not all_modes:
+        raise Exception("No display modes")
+
+    # If we don't have a current mode, use the default mode instead.
+    if not current_mode:
+        default_modes = [
+            m for m in all_modes if CGDisplayModeGetIOFlags(m) & kDisplayModeDefaultFlag
+        ]
+        if not default_modes:
+            raise Exception("No default display mode found")
+        current_mode = default_modes[0]
+        assert current_mode is not None
+
+        if get_size(current_mode) == get_pixel_size(current_mode):
+            return current_mode
+
+    candidates = [
+        m
+        for m in all_modes
+        if CGDisplayModeIsUsableForDesktopGUI(m) and get_size(m) == get_pixel_size(m)
+    ]
+    if not candidates:
+        raise Exception("No suitable display modes")
+
+    same_size_candidates = [
+        m for m in candidates if get_size(m) == get_size(current_mode)
+    ]
+    same_pixel_size_candidates = [
+        m for m in candidates if get_pixel_size(m) == get_pixel_size(current_mode)
+    ]
+
+    if same_size_candidates:
+        candidates = same_size_candidates
+    elif same_pixel_size_candidates:
+        candidates = same_pixel_size_candidates
+
+    return min(
+        candidates,
+        key=lambda m: calculate_mode_similarity_score(m, current_mode),
+    )
+
+
+def set_color_profiles(profile_url: NSURL, *, dry_run: bool = False) -> bool:
+    max_displays = 10
+
+    (err, display_ids, display_count) = CGGetOnlineDisplayList(max_displays, None, None)
+    if err != kCGErrorSuccess:
+        raise ValueError(err)
+
+    display_uuids = [CGDisplayCreateUUIDFromDisplayID(d) for d in display_ids]
+
+    for display_id, display_uuid in zip(display_ids, display_uuids):
+        if dry_run:
+            print(
+                f"Would set color profile for display {display_id} to {profile_url.path()}"
+            )
+        else:
+            profile_info = {kColorSyncDeviceDefaultProfileID: profile_url}
+            success = ColorSyncDeviceSetCustomProfiles(
+                kColorSyncDisplayDeviceClass,
+                display_uuid,
+                profile_info,
+            )
+            if not success:
+                raise Exception(f"failed to set profile on {display_uuid}")
+            print(f"Set color profile for display {display_id}")
+
+    return True
+
+
+def set_display_modes(*, dry_run: bool = False) -> bool:
+    max_displays = 10
+
+    err, display_ids, display_count = CGGetOnlineDisplayList(max_displays, None, None)
+    if err != kCGErrorSuccess:
+        raise ValueError(err)
+
+    if dry_run:
+        for display_id in display_ids:
+            best_mode = find_best_unscaled_mode(display_id)
+            best_size = get_size(best_mode)
+            print(f"Would change display {display_id} to {best_size}")
+        return True
+
+    err, config_ref = CGBeginDisplayConfiguration(None)
+    if err != kCGErrorSuccess:
+        raise Exception("Failed to begin display configuration")
+
+    try:
+        for display_id in display_ids:
+            best_mode = find_best_unscaled_mode(display_id)
+            best_size = get_size(best_mode)
+
+            err = CGConfigureDisplayWithDisplayMode(
+                config_ref, display_id, best_mode, None
+            )
+            if err != kCGErrorSuccess:
+                raise Exception(
+                    f"Failed to configure mode for display {display_id}: {err}"
+                )
+
+            print(f"Configured display {display_id} mode to {best_size}")
+
+    except Exception:
+        CGCancelDisplayConfiguration(config_ref)
+        raise
+
+    else:
+        err = CGCompleteDisplayConfiguration(config_ref, kCGConfigurePermanently)
+        if err != kCGErrorSuccess:
+            raise Exception(f"Failed to complete display configuration: {err}")
+
+        print("Display configuration applied permanently")
+
+    return True
+
+
+def create_parser() -> argparse.ArgumentParser:
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--dry-run",
+        action="store_true",
+        help="Show what would be done without making changes",
+    )
+    parser.add_argument(
+        "--no-color-profile",
+        action="store_false",
+        help="Don't set color profiles",
+    )
+    parser.add_argument(
+        "--no-display-mode",
+        action="store_false",
+        help="Don't set display mode",
+    )
+    parser.add_argument(
+        "--profile-path",
+        default="/System/Library/ColorSync/Profiles/sRGB Profile.icc",
+        help="Path to color profile to use (default: sRGB)",
+    )
+    return parser
+
+
+def run(venv: Any, **kwargs: Any) -> None:
+    profile_url = NSURL.fileURLWithPath_(kwargs["profile_path"])
+    dry_run = kwargs["dry_run"]
+
+    if not kwargs["no_color_profile"]:
+        set_color_profiles(profile_url, dry_run=dry_run)
+
+    if not kwargs["no_display_mode"]:
+        set_display_modes(dry_run=dry_run)