feat: 'impacted' task functional and tested (#2)

* implement

* go back to simpler

* no more root module

* fix

* fix

* fix

* fix

* fix

* fix

Author: alexeagle

.github/workflows/ci.yaml

@@ -22,16 +22,10 @@ jobs:
       - uses: actions/checkout@v5
       - uses: bazel-contrib/setup-bazel@0.15.0
       - name: Install Aspect CLI
-        uses: jaxxstorm/action-install-gh-release@v2.1.0
-        with:
-          repo: aspect-build/aspect-cli
-          tag: 2025.42.8
-          asset-name: aspect-cli
-          platform: unknown_linux
-          arch: x86_64
-          extension-matching: disable
-          rename-to: aspect
-          chmod: 0755
+        run: |
+          curl -LO https://github.com/aspect-build/aspect-cli/releases/download/v2025.46.20/aspect-cli-x86_64-unknown-linux-musl
+          chmod +x aspect-cli-x86_64-unknown-linux-musl
+          mv aspect-cli-x86_64-unknown-linux-musl /usr/local/bin/aspect
       - name: Test
         working-directory: example
         shell: sh

MODULE.aspect

@@ -0,0 +1,2 @@
+"Public API re-export"
+use_task("bazel-diff.axl", "impacted")

README.md

@@ -1,6 +1,6 @@
-# `aspect affected`
+# `aspect impacted`
 
-This task lets you run only the tests which are "affected" by changes to the sources.
+This task lets you run only the tests which are "impacted" by changes to the sources.
 
 It uses the popular Tinder/bazel-diff utility.
 As they document on https://github.com/Tinder/bazel-diff#getting-started:

bazel-diff.axl

@@ -1,28 +1,39 @@
-"""Calculate affected targets from the BASE commit
+"""Calculate impacted targets from the BASE commit
 
 Based on
 https://github.com/Tinder/bazel-diff/blob/master/bazel-diff-example.sh
 """
 def exec(command):
     return command.stdout("piped").spawn().wait_with_output().stdout.strip()
 
+# buildifier: disable=function-docstring
+def checkout_merge_base(std: std.Std):
+    out = std.io.stdout
+    out.write("Checking out merge base...\n")
+    current_revision = exec(std.process.command("git").args(["rev-parse", "HEAD"]))
+    merge_base = exec(std.process.command("git").args(["merge-base", "HEAD", "origin/main"]))
+    checkout = std.process.command("git").args(["checkout", merge_base, "--quiet"]).spawn()
+    if checkout.wait().success:
+        return merge_base, current_revision, None
+    else:
+        return None, None, checkout.stderr
 
-def impl(ctx: task_context):
-    out = ctx.std.io.stdout
-    out.write("Building bazel-diff executable...\n")
-    build = ctx.build(
-        ctx.args.bazel_diff_cli or "//tools:bazel-diff",
-        events = True,
-        bazel_flags = ["--build_runfile_links"],
+# buildifier: disable=function-docstring
+def impl(ctx: TaskContext):
+    ctx.std.io.stdout.write("Building %s executable...\n" % ctx.args.bazel_diff_cli)
+    build = ctx.bazel.build(
+        ctx.args.bazel_diff_cli,
+        build_events = True,
+        flags = ["--build_runfile_links"],
     )
     (bazel_diff_command, runfiles) = (None, None)
-    for event in build.events():
-        if event.type == "named_set_of_files":
+    for event in build.build_events():
+        if event.kind == "named_set_of_files":
             for file in event.payload.files:
-                if len(file.path_prefix) == 0 or file.file.uri.endswith(".jar"):
+                if len(file.path_prefix) == 0 or file.file.endswith(".jar"):
                     continue
-                runfiles = file.file.uri.removeprefix("file://") + ".runfiles"
-                bazel_diff_command = file.file.uri.removeprefix("file://")
+                runfiles = file.file.removeprefix("file://") + ".runfiles"
+                bazel_diff_command = file.file.removeprefix("file://")
     if not bazel_diff_command:
         ctx.std.io.stderr.write("Error finding bazel-diff executable")
         return 1
@@ -37,18 +48,16 @@ def impl(ctx: task_context):
         .spawn() \
         .wait()
 
-    out.write("Checking out merge base...\n")
-    current_revision = exec(ctx.std.process.command("git").args(["rev-parse", "HEAD"]))
-    merge_base = exec(ctx.std.process.command("git").args(["merge-base", "HEAD", "origin/main"]))
-    checkout = ctx.std.process.command("git").args(["checkout", merge_base, "--quiet"]).spawn().wait()
-    if not checkout.success:
-        ctx.std.io.err.write("Error checking out merge base: %s" % checkout.stderr)
+    (merge_base, current_revision, error) = checkout_merge_base(ctx.std)
+    if error:
+        ctx.std.io.stderr.write("Error checking out merge base: %s" % error)
         return 1
 
-    out.write("Generating Hashes for Base Revision %s\n" % merge_base)
     starting_hashes_json=ctx.std.env.temp_dir() + "/starting_hashes.json"
     final_hashes_json=ctx.std.env.temp_dir() + "/final_hashes.json"
     impacted_targets_path=ctx.std.env.temp_dir() + "/impacted_targets.txt"
+
+    ctx.std.io.stdout.write("Generating Hashes for Base Revision %s...\n" % merge_base)
     generate_hashes = bazel_diff([
         "generate-hashes",
         "-w", ctx.std.env.current_dir(),
@@ -59,10 +68,10 @@ def impl(ctx: task_context):
         ctx.std.io.stderr.write("Error generating hashes: %s" % generate_hashes.code)
         return 1
 
-    out.write("Restoring current revision...\n")
-    restore = ctx.std.process.command("git").args(["checkout", current_revision, "--quiet"]).spawn().wait()
-    if not restore.success:
-        ctx.std.io.err.write("Error checking out original commit: %s" % checkout.stderr)
+    ctx.std.io.stdout.write("Restoring current revision...\n")
+    restore = ctx.std.process.command("git").args(["checkout", current_revision, "--quiet"]).spawn()
+    if not restore.wait().success:
+        ctx.std.io.stderr.write("Error checking out original commit: %s" % restore.stderr)
         return 1
 
     generate_hashes = bazel_diff([
@@ -86,11 +95,12 @@ def impl(ctx: task_context):
         return 1
 
     ctx.std.io.stdout.write("Impacted Targets for Revision %s: %s" % (current_revision, ctx.std.fs.read_to_string(impacted_targets_path)))
+    # TODO: offer to test the impacted targets by running `bazel test` on them
     return 0
 
-affected = task(
+impacted = task(
     implementation = impl,
     args = {
-        "bazel_diff_cli": args.string(),
+        "bazel_diff_cli": args.string(default = "//tools:bazel-diff"),
     }
 )

example/.bazelrc

@@ -0,0 +1,4 @@
+# Repository rules, such as rules_jvm_external: put Bazel's JDK on the path.
+# Avoids non-hermeticity from dependency on a JAVA_HOME pointing at a system JDK
+# see https://github.com/bazelbuild/rules_jvm_external/issues/445
+common --repo_env="JAVA_HOME=../bazel_tools/jdk"

example/.gitignore

@@ -0,0 +1 @@
+bazel-*

example/MODULE.aspect

@@ -0,0 +1,5 @@
+axl_local_dep(
+    name = "impacted",
+    path = "..",
+    auto_use_tasks = True,
+)

example/MODULE.bazel

@@ -0,0 +1,10 @@
+bazel_dep(name = "rules_java", version = "8.16.1")
+
+http_jar = use_repo_rule("@bazel_tools//tools/build_defs/repo:http.bzl", "http_jar")
+http_jar(
+    name = "bazel-diff",
+    urls = [
+        "https://github.com/Tinder/bazel-diff/releases/download/10.1.0/bazel-diff_deploy.jar"
+    ],
+    integrity = "sha256-1UKqi+n0hVABtd3hE8A7kmRJO9YAlESg+AWUx6zyar4=",
+)