Auto merge of #15013 - servo:notify-command, r=emilio

Add config to do desktop notifications by running an abitrary command.

<!-- Please describe your changes on the following line: -->

I now have an usual setup where I use a (fast) remote machine for building, and I’m adding a hack to forward end-of-build notifications back to my laptop. This is the motivation for this change, but I kept it general enough that it could be used in other situations.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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python/servo/build_commands.py

@@ -92,24 +92,39 @@ def notify_darwin(title, text):
         raise Exception("Optional Python module 'pyobjc' is not installed.")
 
 
-def notify_build_done(elapsed, success=True):
+def notify_with_command(command):
+    def notify(title, text):
+        if call([command, title, text]) != 0:
+            raise Exception("Could not run '%s'." % command)
+    return notify
+
+
+def notify_build_done(config, elapsed, success=True):
     """Generate desktop notification when build is complete and the
     elapsed build time was longer than 30 seconds."""
     if elapsed > 30:
-        notify("Servo build", "%s in %s" % ("Completed" if success else "FAILED", format_duration(elapsed)))
+        notify(config, "Servo build",
+               "%s in %s" % ("Completed" if success else "FAILED", format_duration(elapsed)))
 
 
-def notify(title, text):
+def notify(config, title, text):
     """Generate a desktop notification using appropriate means on
     supported platforms Linux, Windows, and Mac OS.  On unsupported
-    platforms, this function acts as a no-op."""
-    platforms = {
-        "linux": notify_linux,
-        "linux2": notify_linux,
-        "win32": notify_win,
-        "darwin": notify_darwin
-    }
-    func = platforms.get(sys.platform)
+    platforms, this function acts as a no-op.
+
+    If notify-command is set in the [tools] section of the configuration,
+    that is used instead."""
+    notify_command = config["tools"].get("notify-command")
+    if notify_command:
+        func = notify_with_command(notify_command)
+    else:
+        platforms = {
+            "linux": notify_linux,
+            "linux2": notify_linux,
+            "win32": notify_win,
+            "darwin": notify_darwin
+        }
+        func = platforms.get(sys.platform)
 
     if func is not None:
         try:
@@ -324,7 +339,7 @@ class MachCommands(CommandBase):
                         pass
 
         # Generate Desktop Notification if elapsed-time > some threshold value
-        notify_build_done(elapsed, status == 0)
+        notify_build_done(self.config, elapsed, status == 0)
 
         print("Build %s in %s" % ("Completed" if status == 0 else "FAILED", format_duration(elapsed)))
         return status
@@ -375,7 +390,7 @@ class MachCommands(CommandBase):
         elapsed = time() - build_start
 
         # Generate Desktop Notification if elapsed-time > some threshold value
-        notify_build_done(elapsed)
+        notify_build_done(self.config, elapsed)
 
         print("CEF build completed in %s" % format_duration(elapsed))
 
@@ -430,7 +445,7 @@ class MachCommands(CommandBase):
         elapsed = time() - build_start
 
         # Generate Desktop Notification if elapsed-time > some threshold value
-        notify_build_done(elapsed)
+        notify_build_done(self.config, elapsed)
 
         print("GeckoLib build completed in %s" % format_duration(elapsed))
 

servobuild.example

@@ -27,6 +27,12 @@ system-cargo = false
 # Defaults to true
 rustc-with-gold = true
 
+# If uncommented, this command is used instead of the platform’s default
+# to notify at the end of a compilation that took a long time.
+# This is the name or path of an executable called with two arguments:
+# the summary and content of the notification.
+#notify-command = "notify-send"
+
 [build]
 # Set "mode = dev" or use `mach build --dev` to build the project with warning.
 # or Set "mode = release" or use `mach build --release` for optimized build.