build(client): scope test jobs to changed packages

build-tools/packages/build-cli/docs/check.md

@@ -4,6 +4,7 @@
 Check commands are used to verify repo state, apply policy, etc.
 
 * [`flub check buildVersion`](#flub-check-buildversion)
+* [`flub check changedPackages`](#flub-check-changedpackages)
 * [`flub check changeset`](#flub-check-changeset)
 * [`flub check latestVersions VERSION PACKAGE_OR_RELEASE_GROUP`](#flub-check-latestversions-version-package_or_release_group)
 * [`flub check layers`](#flub-check-layers)
@@ -66,6 +67,35 @@ DESCRIPTION
 
 _See code: [src/commands/check/buildVersion.ts](https://github.com/microsoft/FluidFramework/blob/main/build-tools/packages/build-cli/src/commands/check/buildVersion.ts)_
 
+## `flub check changedPackages`
+
+Computes Azure DevOps output variables used by pipelines to conditionally skip tests.
+
+```
+USAGE
+  $ flub check changedPackages [--json] [-v | --quiet] [--targetBranch <value>] [--searchPath <value>]
+
+FLAGS
+  --searchPath=<value>    Path used to locate the build project. Defaults to the current working directory.
+  --targetBranch=<value>  [env: TARGET_BRANCH] Target branch to compare against. Defaults to the TARGET_BRANCH
+                          environment variable.
+
+LOGGING FLAGS
+  -v, --verbose  Enable verbose logging.
+      --quiet    Disable all logging.
+
+GLOBAL FLAGS
+  --json  Format output as json.
+
+DESCRIPTION
+  Computes Azure DevOps output variables used by pipelines to conditionally skip tests.
+
+  Compares the current PR branch to the merge base with a target branch, then emits 'shouldRunTests' and
+  'scopedPnpmFilter' as Azure DevOps output variables. Unexpected errors conservatively fall back to a full test run.
+```
+
+_See code: [src/commands/check/changedPackages.ts](https://github.com/microsoft/FluidFramework/blob/main/build-tools/packages/build-cli/src/commands/check/changedPackages.ts)_
+
 ## `flub check changeset`
 
 Checks if a changeset was added when compared against a branch. This is used in CI to enforce that changesets are present for a PR.

build-tools/packages/build-cli/src/commands/check/changedPackages.ts

@@ -0,0 +1,241 @@
+/*!
+ * Copyright (c) Microsoft Corporation and contributors. All rights reserved.
+ * Licensed under the MIT License.
+ */
+
+import path from "node:path";
+
+import {
+	getChangedSinceRef,
+	getMergeBaseRemote,
+	getPackageDirsAtRef,
+	getRemote,
+	isFileInPackageDir,
+} from "@fluid-tools/build-infrastructure";
+import { Flags } from "@oclif/core";
+
+import {
+	formatLogIssue,
+	formatSetVariable,
+} from "../../library/azureDevops/pipelineCommands.js";
+import { normalizeTargetBranch } from "../../library/branches.js";
+import { BaseCommandWithBuildProject } from "../../library/commands/base.js";
+
+/**
+ * Full-run trigger patterns. A diff touching any of these paths forces running
+ * every package's tests. Keep this conservative since these files can affect
+ * dependency resolution, build behavior, or pipeline behavior across packages.
+ */
+const fullRunPatterns: readonly RegExp[] = [
+	/^package\.json$/,
+	/^pnpm-lock\.yaml$/,
+	/^pnpm-workspace\.yaml$/,
+	/^\.pnpmfile\.cjs$/,
+	/^\.npmrc$/,
+	/^\.nvmrc$/,
+	/^fluidBuild\.config\.cjs$/,
+	/^tsconfig[^/]*\.json$/,
+	/^biome\./,
+	/^tools\//,
+	/^common\//,
+	/^scripts\//,
+	/^\.changeset\/config\.json$/,
+];
+
+/**
+ * Result of computing which packages have changed since the target branch.
+ *
+ * The same shape is returned both for full-run fallbacks (e.g. unexpected errors or trigger-pattern
+ * matches) and for the normal scoped-filter case. Consumers can inspect {@link forcedFullRunPattern}
+ * to disambiguate.
+ */
+export interface ChangedPackagesResult {
+	/** Whether any tests should run at all. `false` only when no changed file maps to a workspace package. */
+	shouldRunTests: boolean;
+	/** The computed `pnpm --filter` expression, or an empty string for full / no-op runs. */
+	scopedPnpmFilter: string;
+	/** The (normalized) target branch the comparison was performed against. */
+	targetBranch: string;
+	/** The merge-base commit between HEAD and the target branch, when it could be determined. */
+	mergeBase?: string;
+	/** The list of files that changed since the merge base. Empty on the error fallback path. */
+	changedFiles: string[];
+	/** The source of the first {@link fullRunPatterns} entry that matched a changed file, if any. */
+	forcedFullRunPattern?: string;
+	/** Number of workspace packages reported as changed by `getChangedSinceRef`. */
+	changedPackageCount: number;
+}
+
+/**
+ * Returns the first pattern in `patterns` that matches any path in `files`, or `undefined` if
+ * none match.
+ */
+function findFullRunPatternMatch(
+	files: readonly string[],
+	patterns: readonly RegExp[],
+): RegExp | undefined {
+	for (const pattern of patterns) {
+		if (files.some((file) => pattern.test(file))) {
+			return pattern;
+		}
+	}
+	return undefined;
+}
+
+export default class CheckChangedPackagesCommand extends BaseCommandWithBuildProject<
+	typeof CheckChangedPackagesCommand
+> {
+	static readonly summary =
+		"Computes Azure DevOps output variables used by pipelines to conditionally skip tests.";
+
+	static readonly description =
+		"Compares the current PR branch to the merge base with a target branch, then emits 'shouldRunTests' and 'scopedPnpmFilter' as Azure DevOps output variables. Unexpected errors conservatively fall back to a full test run.";
+
+	static readonly enableJsonFlag = true;
+
+	static readonly flags = {
+		targetBranch: Flags.string({
+			description:
+				"Target branch to compare against. Defaults to the TARGET_BRANCH environment variable.",
+			env: "TARGET_BRANCH",
+		}),
+		searchPath: Flags.directory({
+			description:
+				"Path used to locate the build project. Defaults to the current working directory.",
+			exists: true,
+		}),
+		...BaseCommandWithBuildProject.flags,
+	} as const;
+
+	public async run(): Promise<ChangedPackagesResult> {
+		const targetBranch = normalizeTargetBranch(
+			this.flags.targetBranch ?? process.env.TARGET_BRANCH ?? "",
+		);
+
+		if (targetBranch === "") {
+			return this.fallbackFullRun("TARGET_BRANCH not set;", targetBranch);
+		}
+
+		this.info(`Target branch: ${targetBranch}`);
+
+		try {
+			const buildProject = this.getBuildProject(
+				path.resolve(this.flags.searchPath ?? process.cwd()),
+			);
+			const git = await buildProject.getGitRepository();
+			const remote = await getRemote(git, buildProject.upstreamRemotePartialUrl);
+			if (remote === undefined) {
+				return this.fallbackFullRun(
+					`Could not find upstream remote for ${buildProject.upstreamRemotePartialUrl};`,
+					targetBranch,
+				);
+			}
+
+			await git.fetch([remote, targetBranch]);
+			const mergeBase = await getMergeBaseRemote(
+				git,
+				targetBranch,
+				remote,
+				"HEAD",
+				(message) => this.info(message),
+			);
+			this.info(`Merge base: ${mergeBase}`);
+
+			const changed = await getChangedSinceRef(buildProject, targetBranch, remote);
+			const changedFiles = changed.files;
+			this.info(`Changed files (${changedFiles.length}):`);
+			for (const file of changedFiles.slice(0, 30)) {
+				this.info(file);
+			}
+			if (changedFiles.length > 30) {
+				this.info(`... and ${changedFiles.length - 30} more`);
+			}
+
+			const match = findFullRunPatternMatch(changedFiles, fullRunPatterns);
+			if (match !== undefined) {
+				this.info(`Match for full-run pattern '${match.source}' - forcing full test run.`);
+				this.emitVsoOutputs(true, "");
+				return {
+					shouldRunTests: true,
+					scopedPnpmFilter: "",
+					targetBranch,
+					mergeBase,
+					changedFiles,
+					forcedFullRunPattern: match.source,
+					changedPackageCount: changed.packages.length,
+				};
+			}
+
+			// Union of package directories at the merge-base tree and the current working tree so
+			// that packages added, removed, or moved between the two refs are all considered.
+			const historicalDirs = await getPackageDirsAtRef(git, mergeBase);
+			const currentDirs = await getPackageDirsAtRef(git);
+			const packageDirs = new Set([...historicalDirs, ...currentDirs]);
+
+			if (!changedFiles.some((file) => isFileInPackageDir(file, packageDirs))) {
+				this.logWarning(
+					`No changed files mapped to a workspace package - skipping all test execution. Files considered (${changedFiles.length}):`,
+				);
+				for (const file of changedFiles) {
+					this.info(`  ${file}`);
+				}
+				this.emitVsoOutputs(false, "");
+				return {
+					shouldRunTests: false,
+					scopedPnpmFilter: "",
+					targetBranch,
+					mergeBase,
+					changedFiles,
+					changedPackageCount: 0,
+				};
+			}
+
+			const scopedPnpmFilter = `...[${mergeBase}]`;
+			this.info(`Computed pnpm filter: ${scopedPnpmFilter}`);
+			this.emitVsoOutputs(true, scopedPnpmFilter);
+			return {
+				shouldRunTests: true,
+				scopedPnpmFilter,
+				targetBranch,
+				mergeBase,
+				changedFiles,
+				changedPackageCount: changed.packages.length,
+			};
+		} catch (error) {
+			return this.fallbackFullRun(
+				error instanceof Error ? `${error.message};` : `${String(error)};`,
+				targetBranch,
+			);
+		}
+	}
+
+	private emitVsoOutputs(shouldRunTests: boolean, scopedPnpmFilter: string): void {
+		if (this.jsonEnabled()) {
+			return;
+		}
+
+		const flag = shouldRunTests ? "true" : "false";
+		this.log(`shouldRunTests=${flag}`);
+		this.log(`scopedPnpmFilter=${scopedPnpmFilter}`);
+		this.log(formatSetVariable("shouldRunTests", flag, { isOutput: true }));
+		this.log(formatSetVariable("scopedPnpmFilter", scopedPnpmFilter, { isOutput: true }));
+	}
+
+	private logWarning(message: string): void {
+		if (!this.jsonEnabled()) {
+			this.log(formatLogIssue("warning", message));
+		}
+	}
+
+	private fallbackFullRun(reason: string, targetBranch: string): ChangedPackagesResult {
+		this.logWarning(`${reason} Falling back to full test run.`);
+		this.emitVsoOutputs(true, "");
+		return {
+			shouldRunTests: true,
+			scopedPnpmFilter: "",
+			targetBranch,
+			changedFiles: [],
+			changedPackageCount: 0,
+		};
+	}
+}

build-tools/packages/build-cli/src/commands/check/latestVersions.ts

@@ -4,6 +4,7 @@
  */
 
 import { findPackageOrReleaseGroup, packageOrReleaseGroupArg, semverArg } from "../../args.js";
+import { formatSetVariable } from "../../library/azureDevops/pipelineCommands.js";
 import { BaseCommand } from "../../library/commands/base.js";
 import { isLatestInMajor } from "../../library/latestVersions.js";
 
@@ -52,9 +53,9 @@ export default class LatestVersionsCommand extends BaseCommand<typeof LatestVers
 			this.log(
 				`Version ${versionInput.version} is the latest version for major version ${result.majorVersion}`,
 			);
-			this.log(`##vso[task.setvariable variable=shouldDeploy;isoutput=true]true`);
+			this.log(formatSetVariable("shouldDeploy", "true", { isOutput: true }));
 			this.log(
-				`##vso[task.setvariable variable=majorVersion;isoutput=true]${result.majorVersion}`,
+				formatSetVariable("majorVersion", String(result.majorVersion), { isOutput: true }),
 			);
 			return;
 		}
@@ -63,19 +64,19 @@ export default class LatestVersionsCommand extends BaseCommand<typeof LatestVers
 			this.log(
 				`##[warning]skipping deployment stage. input version ${versionInput.version} does not match the latest version ${result.latestVersion}`,
 			);
-			this.log(`##vso[task.setvariable variable=shouldDeploy;isoutput=true]false`);
+			this.log(formatSetVariable("shouldDeploy", "false", { isOutput: true }));
 			this.log(
-				`##vso[task.setvariable variable=majorVersion;isoutput=true]${result.majorVersion}`,
+				formatSetVariable("majorVersion", String(result.majorVersion), { isOutput: true }),
 			);
 			return;
 		}
 
 		this.log(
 			`##[warning]No major version found corresponding to input version ${versionInput.version}`,
 		);
-		this.log(`##vso[task.setvariable variable=shouldDeploy;isoutput=true]false`);
+		this.log(formatSetVariable("shouldDeploy", "false", { isOutput: true }));
 		this.log(
-			`##vso[task.setvariable variable=majorVersion;isoutput=true]${result.majorVersion}`,
+			formatSetVariable("majorVersion", String(result.majorVersion), { isOutput: true }),
 		);
 	}
 }

build-tools/packages/build-cli/src/commands/generate/buildVersion.ts

@@ -8,6 +8,7 @@ import { getIsLatest, getSimpleVersion } from "@fluid-tools/version-tools";
 import { Flags } from "@oclif/core";
 
 import { semverFlag } from "../../flags.js";
+import { formatSetVariable } from "../../library/azureDevops/pipelineCommands.js";
 import { BaseCommand } from "../../library/commands/base.js";
 
 /**
@@ -138,7 +139,7 @@ export default class GenerateBuildVersionCommand extends BaseCommand<
 				? `${simpleVersion}-test-${alphabetaTypePrefix}`
 				: `${simpleVersion}-test`;
 			this.log(`codeVersion=${codeVersion}`);
-			this.log(`##vso[task.setvariable variable=codeVersion;isOutput=true]${codeVersion}`);
+			this.log(formatSetVariable("codeVersion", codeVersion, { isOutput: true }));
 		}
 
 		if (isAlphaOrBetaTypes) {
@@ -154,13 +155,13 @@ export default class GenerateBuildVersionCommand extends BaseCommand<
 		}
 
 		this.log(`version=${version}`);
-		this.log(`##vso[task.setvariable variable=version;isOutput=true]${version}`);
+		this.log(formatSetVariable("version", version, { isOutput: true }));
 
 		if (flags.tag !== undefined) {
 			const isLatest = getIsLatest(flags.tag, version, tags, shouldIncludeInternalVersions);
 			this.log(`isLatest=${isLatest}`);
 			if (isRelease && isLatest === true) {
-				this.log(`##vso[task.setvariable variable=isLatest;isOutput=true]${isLatest}`);
+				this.log(formatSetVariable("isLatest", String(isLatest), { isOutput: true }));
 			}
 		}
 	}