From 1bf27de9fdf4ff291606a7223044fe1e27d56935 Mon Sep 17 00:00:00 2001
From: Eric Amodio <eamodio@gmail.com>
Date: Wed, 1 Jul 2020 02:03:26 -0400
Subject: [PATCH] Adds better ref validation/resolve

---
 src/git/git.ts        | 62 +++++++++++++++++++++------------------------------
 src/git/gitService.ts | 24 ++++++++++----------
 2 files changed, 37 insertions(+), 49 deletions(-)

diff --git a/src/git/git.ts b/src/git/git.ts
index 6ab4b5c..4983a71 100644
--- a/src/git/git.ts
+++ b/src/git/git.ts
@@ -448,38 +448,6 @@ export namespace Git {
 		return git<string>({ cwd: repoPath, configs: ['-c', 'color.branch=false'] }, ...params, ref);
 	}
 
-	export async function cat_file__resolve(repoPath: string, fileName: string, ref: string) {
-		if (GitRevision.isUncommitted(ref)) return ref;
-
-		try {
-			void (await git<string>(
-				{ cwd: repoPath, errors: GitErrorHandling.Throw },
-				'cat-file',
-				'-e',
-				`${ref}:./${fileName}`,
-			));
-			return ref;
-		} catch (ex) {
-			const msg: string = ex?.toString();
-			if (GitErrors.notAValidObjectName.test(msg)) {
-				return GitRevision.deletedOrMissing;
-			}
-
-			return undefined;
-		}
-	}
-
-	export async function cat_file__validate(repoPath: string, ref: string) {
-		if (GitRevision.isUncommitted(ref)) return true;
-
-		try {
-			void (await git<string>({ cwd: repoPath, errors: GitErrorHandling.Throw }, 'cat-file', '-t', ref));
-			return true;
-		} catch (ex) {
-			return false;
-		}
-	}
-
 	export function check_ignore(repoPath: string, ...files: string[]) {
 		return git<string>(
 			{ cwd: repoPath, errors: GitErrorHandling.Ignore, stdin: files.join('\0') },
@@ -922,6 +890,17 @@ export namespace Git {
 		return data.length === 0 ? undefined : data.trim();
 	}
 
+	export async function log__find_object(repoPath: string, objectId: string) {
+		const data = await git<string>(
+			{ cwd: repoPath, errors: GitErrorHandling.Ignore },
+			'log',
+			'-n1',
+			'--format=%H',
+			`--find-object=${objectId}`,
+		);
+		return data.length === 0 ? undefined : data.trim();
+	}
+
 	export async function log__recent(repoPath: string) {
 		const data = await git<string>(
 			{ cwd: repoPath, errors: GitErrorHandling.Ignore },
@@ -1072,11 +1051,6 @@ export namespace Git {
 		return data.length === 0 ? undefined : Number(data.trim()) || undefined;
 	}
 
-	export async function rev_parse(repoPath: string, ref: string): Promise<string | undefined> {
-		const data = await git<string>({ cwd: repoPath, errors: GitErrorHandling.Ignore }, 'rev-parse', ref);
-		return data.length === 0 ? undefined : data.trim();
-	}
-
 	export async function rev_parse__currentBranch(
 		repoPath: string,
 	): Promise<[string, string | undefined] | undefined> {
@@ -1139,6 +1113,20 @@ export namespace Git {
 		}
 	}
 
+	export async function rev_parse__verify(
+		repoPath: string,
+		ref: string,
+		filename?: string,
+	): Promise<string | undefined> {
+		const data = await git<string>(
+			{ cwd: repoPath, errors: GitErrorHandling.Ignore },
+			'rev-parse',
+			'--verify',
+			filename ? `${ref}:./${filename}` : `${ref}^{commit}`,
+		);
+		return data.length === 0 ? undefined : data.trim();
+	}
+
 	export function shortlog(repoPath: string) {
 		return git<string>({ cwd: repoPath }, 'shortlog', '-sne', '--all', '--no-merges');
 	}
diff --git a/src/git/gitService.ts b/src/git/gitService.ts
index d3c3797..ea502e8 100644
--- a/src/git/gitService.ts
+++ b/src/git/gitService.ts
@@ -3144,12 +3144,14 @@ export class GitService implements Disposable {
 	async resolveReference(repoPath: string, ref: string, uri?: Uri): Promise<string>;
 	@log()
 	async resolveReference(repoPath: string, ref: string, fileNameOrUri?: string | Uri) {
-		if (ref == null || ref.length === 0 || ref === GitRevision.deletedOrMissing) return ref;
+		if (ref == null || ref.length === 0 || ref === GitRevision.deletedOrMissing || GitRevision.isUncommitted(ref)) {
+			return ref;
+		}
 
 		if (fileNameOrUri == null) {
 			if (GitRevision.isSha(ref) || !GitRevision.isShaLike(ref) || ref.endsWith('^3')) return ref;
 
-			return (await Git.rev_parse(repoPath, ref)) ?? ref;
+			return (await Git.rev_parse__verify(repoPath, ref)) ?? ref;
 		}
 
 		const fileName =
@@ -3157,15 +3159,10 @@ export class GitService implements Disposable {
 				? fileNameOrUri
 				: Strings.normalizePath(paths.relative(repoPath, fileNameOrUri.fsPath));
 
-		if (GitRevision.isShaParent(ref)) {
-			const parentRef = await Git.log__file_recent(repoPath, fileName, { ref: ref });
-			if (parentRef != null) return parentRef;
-		}
-
-		const ensuredRef = await Git.cat_file__resolve(repoPath, fileName, ref);
-		if (ensuredRef == null) return ref;
+		const blob = await Git.rev_parse__verify(repoPath, ref, fileName);
+		if (blob == null) return ref;
 
-		return ensuredRef;
+		return (await Git.log__find_object(repoPath, blob)) ?? ref;
 	}
 
 	@log()
@@ -3174,8 +3171,11 @@ export class GitService implements Disposable {
 	}
 
 	@log()
-	validateReference(repoPath: string, ref: string) {
-		return Git.cat_file__validate(repoPath, ref);
+	async validateReference(repoPath: string, ref: string) {
+		if (ref == null || ref.length === 0) return false;
+		if (ref === GitRevision.deletedOrMissing || GitRevision.isUncommitted(ref)) return true;
+
+		return (await Git.rev_parse__verify(repoPath, ref)) != null;
 	}
 
 	stageFile(repoPath: string, fileName: string): Promise<string>;