Auto merge of #23383 - jdm:tc-parent, r=jdm

Reuse more tasks

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etc/taskcluster/decision_task.py

@@ -193,12 +193,12 @@ def linux_tidy_unit_docs():
             git bundle create docs.bundle HEAD
         """)
         .with_artifacts("/repo/target/doc/docs.bundle")
-        .find_or_create("docs." + CONFIG.git_sha)
+        .find_or_create("docs." + CONFIG.task_id())
     )
 
 
 def upload_docs():
-    docs_build_task_id = decisionlib.Task.find("docs." + CONFIG.git_sha)
+    docs_build_task_id = decisionlib.Task.find("docs." + CONFIG.task_id())
     return (
         linux_task("Upload docs to GitHub Pages")
         .with_treeherder("Linux x64", "DocUpload")
@@ -233,7 +233,7 @@ def macos_unit():
             ./mach package --dev
             ./etc/ci/lockfile_changed.sh
         """)
-        .find_or_create("macos_unit." + CONFIG.git_sha)
+        .find_or_create("macos_unit." + CONFIG.task_id())
     )
 
 
@@ -266,7 +266,7 @@ def android_arm32_dev_from_macos():
             ./mach bootstrap-android --accept-all-licences --build
             ./mach build --android --dev --verbose
         """)
-        .find_or_create("android_arm32_dev.macos." + CONFIG.git_sha)
+        .find_or_create("android_arm32_dev.macos." + CONFIG.task_id())
     )
 
 
@@ -279,7 +279,7 @@ def android_arm32_dev():
             ./etc/ci/lockfile_changed.sh
             python ./etc/ci/check_dynamic_symbols.py
         """)
-        .find_or_create("android_arm32_dev." + CONFIG.git_sha)
+        .find_or_create("android_arm32_dev." + CONFIG.task_id())
     )
 
 
@@ -303,7 +303,7 @@ def android_nightly():
             "/repo/target/android/i686-linux-android/release/servoapp.apk",
             "/repo/target/android/i686-linux-android/release/servoview.aar",
         )
-        .find_or_create("build.android_nightlies." + CONFIG.git_sha)
+        .find_or_create("build.android_nightlies." + CONFIG.task_id())
     )
 
 
@@ -316,7 +316,7 @@ def android_arm32_release():
             "/repo/target/android/armv7-linux-androideabi/release/servoapp.apk",
             "/repo/target/android/armv7-linux-androideabi/release/servoview.aar",
         )
-        .find_or_create("build.android_armv7_release." + CONFIG.git_sha)
+        .find_or_create("build.android_armv7_release." + CONFIG.task_id())
     )
 
 
@@ -329,7 +329,7 @@ def android_x86_release():
             "/repo/target/android/i686-linux-android/release/servoapp.apk",
             "/repo/target/android/i686-linux-android/release/servoview.aar",
         )
-        .find_or_create("build.android_x86_release." + CONFIG.git_sha)
+        .find_or_create("build.android_x86_release." + CONFIG.task_id())
     )
 
 
@@ -352,7 +352,7 @@ def android_x86_wpt():
                 /_mozilla/mozilla/DOMParser.html \
                 /_mozilla/mozilla/webgl/context_creation_error.html
         """)
-        .find_or_create("android_x86_release." + CONFIG.git_sha)
+        .find_or_create("android_x86_release." + CONFIG.task_id())
     )
 
 
@@ -366,7 +366,7 @@ def windows_x86():
         .with_script(
             "python mach build --dev --target i686-pc-windows-msvc",
         )
-        .find_or_create("build.windows_x86_dev." + CONFIG.git_sha)
+        .find_or_create("build.windows_x86_dev." + CONFIG.task_id())
     )
 
 
@@ -385,7 +385,7 @@ def windows_unit():
         )
         .with_artifacts("repo/target/debug/msi/Servo.exe",
                         "repo/target/debug/msi/Servo.zip")
-        .find_or_create("build.windows_x64_dev." + CONFIG.git_sha)
+        .find_or_create("build.windows_x64_dev." + CONFIG.task_id())
     )
 
 
@@ -397,7 +397,7 @@ def windows_release():
                      "mach package --release")
         .with_artifacts("repo/target/release/msi/Servo.exe",
                         "repo/target/release/msi/Servo.zip")
-        .find_or_create("build.windows_x64_release." + CONFIG.git_sha)
+        .find_or_create("build.windows_x64_release." + CONFIG.task_id())
     )
 
 
@@ -413,7 +413,7 @@ def windows_nightly():
                      "mach upload-nightly windows-msvc --secret-from-taskcluster")
         .with_artifacts("repo/target/release/msi/Servo.exe",
                         "repo/target/release/msi/Servo.zip")
-        .find_or_create("build.windows_x64_nightly." + CONFIG.git_sha)
+        .find_or_create("build.windows_x64_nightly." + CONFIG.task_id())
     )
 
 
@@ -430,7 +430,7 @@ def linux_nightly():
             "./mach upload-nightly linux --secret-from-taskcluster",
         )
         .with_artifacts("/repo/target/release/servo-tech-demo.tar.gz")
-        .find_or_create("build.linux_x64_nightly" + CONFIG.git_sha)
+        .find_or_create("build.linux_x64_nightly" + CONFIG.task_id())
     )
 
 
@@ -447,7 +447,7 @@ def linux_wpt():
                 target/release/build/osmesa-src-*/out/lib/gallium
         """)
         .with_artifacts("/target.tar.gz")
-        .find_or_create("build.linux_x64_release~assertions" + CONFIG.git_sha)
+        .find_or_create("build.linux_x64_release~assertions" + CONFIG.task_id())
     )
     def linux_run_task(name):
         return linux_task(name).with_dockerfile(dockerfile_path("run"))
@@ -470,7 +470,7 @@ def macos_nightly():
             "./mach upload-nightly mac --secret-from-taskcluster",
         )
         .with_artifacts("repo/target/release/servo-tech-demo.dmg")
-        .find_or_create("build.mac_x64_nightly." + CONFIG.git_sha)
+        .find_or_create("build.mac_x64_nightly." + CONFIG.task_id())
     )
 
 
@@ -500,7 +500,7 @@ def update_wpt():
             ./etc/ci/update-wpt-checkout open-pr
             ./etc/ci/update-wpt-checkout cleanup
         """)
-        .find_or_create("wpt_update." + CONFIG.git_sha)
+        .find_or_create("wpt_update." + CONFIG.task_id())
     )
 
 
@@ -518,7 +518,7 @@ def macos_release_build():
                 target/release/build/osmesa-src-*/out/src/mapi/shared-glapi/.libs
         """)
         .with_artifacts("repo/target.tar.gz")
-        .find_or_create("build.macos_x64_release." + CONFIG.git_sha)
+        .find_or_create("build.macos_x64_release." + CONFIG.task_id())
     )
 
 
@@ -606,7 +606,7 @@ def wpt_chunks(platform, make_chunk_task, build_task, total_chunks, processes,
             if word.endswith(".log")
         ])
         platform_id = platform.replace(" ", "_").lower()
-        task.find_or_create("%s_wpt_%s.%s" % (platform_id, this_chunk, CONFIG.git_sha))
+        task.find_or_create("%s_wpt_%s.%s" % (platform_id, this_chunk, CONFIG.task_id()))
 
 
 def daily_tasks_setup():
@@ -845,7 +845,7 @@ def magicleap_dev():
             ./mach build --magicleap --dev
             env -u DYLD_LIBRARY_PATH ./mach package --magicleap --dev
         """)
-        .find_or_create("build.magicleap_dev." + CONFIG.git_sha)
+        .find_or_create("build.magicleap_dev." + CONFIG.task_id())
     )
 
 
@@ -860,7 +860,7 @@ def magicleap_nightly():
             ./mach upload-nightly magicleap --secret-from-taskcluster
         """)
         .with_artifacts("repo/target/magicleap/aarch64-linux-android/release/Servo2D.mpk")
-        .find_or_create("build.magicleap_nightly." + CONFIG.git_sha)
+        .find_or_create("build.magicleap_nightly." + CONFIG.task_id())
     )
 
 

etc/taskcluster/decisionlib.py

@@ -57,6 +57,26 @@ class Config:
         self.git_ref = os.environ.get("GIT_REF")
         self.git_sha = os.environ.get("GIT_SHA")
 
+    def task_id(self):
+        if hasattr(self, "_task_id"):
+            return self._task_id
+        # If the head commit is a merge, we want to generate a unique task id which incorporates
+        # the merge parents rather that the actual sha of the merge commit. This ensures that tasks
+        # can be reused if the tree is in an identical state. Otherwise, if the head commit is
+        # not a merge, we can rely on the head commit sha for that purpose.
+        raw_commit = subprocess.check_output(["git", "cat-file", "commit", "HEAD"])
+        parent_commits = [
+            value.decode("utf8")
+            for line in raw_commit.split(b"\n")
+            for key, _, value in [line.partition(b" ")]
+            if key == b"parent"
+        ]
+        if len(parent_commits) > 1:
+            self._task_id = "-".join(parent_commits) # pragma: no cover
+        else:
+            self._task_id = self.git_sha # pragma: no cover
+        return self._task_id
+
     def git_sha_is_current_head(self):
         output = subprocess.check_output(["git", "rev-parse", "HEAD"])
         self.git_sha = output.decode("utf8").strip()