Fixes alignment issue when showing changes diff

Adds changes diff for first commit changes

src/annotations/blameAnnotationProvider.ts

@@ -160,7 +160,7 @@ export abstract class BlameAnnotationProviderBase extends AnnotationProviderBase
 			await Promise.all([
 				providers.details ? this.getDetailsHoverMessage(commit, document) : undefined,
 				providers.changes
-					? Hovers.changesMessage(commit, await GitUri.fromUri(document.uri), position.line)
+					? Hovers.changesMessage(commit, await GitUri.fromUri(document.uri), position.line, document)
 					: undefined,
 			])
 		).filter(<T>(m?: T): m is T => Boolean(m));

src/env/node/git/localGitProvider.ts

@@ -1637,7 +1637,6 @@ export class LocalGitProvider implements GitProvider, Disposable {
 				renames: true,
 				similarityThreshold: this.container.config.advanced.similarityThreshold,
 			});
-			// }
 
 			const diff = GitDiffParser.parse(data);
 			return diff;
@@ -1761,7 +1760,7 @@ export class LocalGitProvider implements GitProvider, Disposable {
 			const hunk = diff.hunks.find(c => c.current.position.start <= line && c.current.position.end >= line);
 			if (hunk == null) return undefined;
 
-			return hunk.lines[line - hunk.current.position.start];
+			return hunk.lines[line - Math.min(hunk.current.position.start, hunk.previous.position.start)];
 		} catch (ex) {
 			return undefined;
 		}

src/git/models/reference.ts

@@ -2,8 +2,6 @@ import { GlyphChars } from '../../constants';
 import { Container } from '../../container';
 import { GitBranch } from './branch';
 
-const emptyStr = '';
-
 const rangeRegex = /^(\S*?)(\.\.\.?)(\S*)\s*$/;
 const shaLikeRegex = /(^[0-9a-f]{40}([\^@~:]\S*)?$)|(^[0]{40}(:|-)$)/;
 const shaRegex = /(^[0-9a-f]{40}$)|(^[0]{40}(:|-)$)/;
@@ -13,7 +11,7 @@ const uncommittedRegex = /^[0]{40}(?:[\^@~:]\S*)?:?$/;
 const uncommittedStagedRegex = /^[0]{40}([\^@~]\S*)?:$/;
 
 function isMatch(regex: RegExp, ref: string | undefined) {
-	return ref == null || ref.length === 0 ? false : regex.test(ref);
+	return !ref ? false : regex.test(ref);
 }
 
 export namespace GitRevision {
@@ -46,11 +44,11 @@ export namespace GitRevision {
 	}
 
 	export function isUncommitted(ref: string | undefined) {
-		return isMatch(uncommittedRegex, ref);
+		return ref === uncommitted || isMatch(uncommittedRegex, ref);
 	}
 
 	export function isUncommittedStaged(ref: string | undefined): boolean {
-		return isMatch(uncommittedStagedRegex, ref);
+		return ref === uncommittedStaged || isMatch(uncommittedStagedRegex, ref);
 	}
 
 	export function shorten(
@@ -65,7 +63,7 @@ export namespace GitRevision {
 	) {
 		if (ref === deletedOrMissing) return '(deleted)';
 
-		if (ref == null || ref.length === 0) return strings.working ?? emptyStr;
+		if (!ref) return strings.working ?? '';
 		if (isUncommitted(ref)) {
 			return isUncommittedStaged(ref)
 				? strings.uncommittedStaged ?? 'Index'

src/git/parsers/diffParser.ts

@@ -37,14 +37,14 @@ export class GitDiffParser {
 					// Stops excessive memory usage -- https://bugs.chromium.org/p/v8/issues/detail?id=2869
 					` ${hunk}`.substr(1),
 					{
-						count: currentCount,
+						count: currentCount === 0 ? 1 : currentCount,
 						position: {
 							start: currentStart,
 							end: currentStart + (currentCount > 0 ? currentCount - 1 : 0),
 						},
 					},
 					{
-						count: previousCount,
+						count: previousCount === 0 ? 1 : previousCount,
 						position: {
 							start: previousStart,
 							end: previousStart + (previousCount > 0 ? previousCount - 1 : 0),
@@ -65,8 +65,17 @@ export class GitDiffParser {
 
 	@debug({ args: false, singleLine: true })
 	static parseHunk(hunk: GitDiffHunk): { lines: GitDiffHunkLine[]; state: 'added' | 'changed' | 'removed' } {
-		const currentLines: (GitDiffLine | undefined)[] = [];
-		const previousLines: (GitDiffLine | undefined)[] = [];
+		const currentStart = hunk.current.position.start;
+		const previousStart = hunk.previous.position.start;
+
+		const currentLines: (GitDiffLine | undefined)[] =
+			currentStart > previousStart
+				? new Array(currentStart - previousStart).fill(undefined, 0, currentStart - previousStart)
+				: [];
+		const previousLines: (GitDiffLine | undefined)[] =
+			previousStart > currentStart
+				? new Array(previousStart - currentStart).fill(undefined, 0, previousStart - currentStart)
+				: [];
 
 		let hasAddedOrChanged;
 		let hasRemoved;
@@ -120,7 +129,7 @@ export class GitDiffParser {
 
 		const hunkLines: GitDiffHunkLine[] = [];
 
-		for (let i = 0; i < currentLines.length; i++) {
+		for (let i = 0; i < Math.max(currentLines.length, previousLines.length); i++) {
 			hunkLines.push({
 				hunk: hunk,
 				current: currentLines[i],

src/hovers/hovers.ts

@@ -1,4 +1,4 @@
-import { CancellationToken, MarkdownString } from 'vscode';
+import { CancellationToken, MarkdownString, TextDocument } from 'vscode';
 import { hrtime } from '@env/hrtime';
 import { DiffWithCommand, ShowQuickCommitCommand } from '../commands';
 import { GlyphChars } from '../constants';
@@ -24,11 +24,13 @@ export namespace Hovers {
 		commit: GitBlameCommit | GitLogCommit,
 		uri: GitUri,
 		editorLine: number,
+		document: TextDocument,
 	): Promise<MarkdownString | undefined> {
 		const documentRef = uri.sha;
 
-		let hunkLine;
-		if (GitBlameCommit.is(commit)) {
+		async function getDiff() {
+			if (!GitBlameCommit.is(commit)) return undefined;
+
 			// TODO: Figure out how to optimize this
 			let ref;
 			if (commit.isUncommitted) {
@@ -37,7 +39,9 @@ export namespace Hovers {
 				}
 			} else {
 				ref = commit.previousSha;
-				if (ref == null) return undefined;
+				if (ref == null) {
+					return `\`\`\`diff\n+ ${document.lineAt(editorLine).text}\n\`\`\``;
+				}
 			}
 
 			const line = editorLine + 1;
@@ -52,7 +56,7 @@ export namespace Hovers {
 
 			editorLine = commitLine.line - 1;
 			// TODO: Doesn't work with dirty files -- pass in editor? or contents?
-			hunkLine = await Container.instance.git.getDiffForLine(uri, editorLine, ref, documentRef);
+			let hunkLine = await Container.instance.git.getDiffForLine(uri, editorLine, ref, documentRef);
 
 			// If we didn't find a diff & ref is undefined (meaning uncommitted), check for a staged diff
 			if (hunkLine == null && ref == null) {
@@ -63,11 +67,11 @@ export namespace Hovers {
 					GitRevision.uncommittedStaged,
 				);
 			}
-		}
 
-		if (hunkLine == null || commit.previousSha == null) return undefined;
+			return hunkLine != null ? getDiffFromHunkLine(hunkLine) : undefined;
+		}
 
-		const diff = getDiffFromHunkLine(hunkLine);
+		const diff = await getDiff();
 
 		let message;
 		let previous;
@@ -91,14 +95,16 @@ export namespace Hovers {
 
 			previous =
 				diffUris.previous.sha == null || diffUris.previous.isUncommitted
-					? `_${GitRevision.shorten(diffUris.previous.sha, {
+					? `  &nbsp;_${GitRevision.shorten(diffUris.previous.sha, {
 							strings: {
 								working: 'Working Tree',
 							},
-					  })}_`
-					: `[$(git-commit) ${GitRevision.shorten(
+					  })}_ &nbsp;${GlyphChars.ArrowLeftRightLong}&nbsp; `
+					: `  &nbsp;[$(git-commit) ${GitRevision.shorten(
+							diffUris.previous.sha || '',
+					  )}](${ShowQuickCommitCommand.getMarkdownCommandArgs(
 							diffUris.previous.sha || '',
-					  )}](${ShowQuickCommitCommand.getMarkdownCommandArgs(diffUris.previous.sha || '')} "Show Commit")`;
+					  )} "Show Commit") &nbsp;${GlyphChars.ArrowLeftRightLong}&nbsp; `;
 
 			current =
 				diffUris.current.sha == null || diffUris.current.isUncommitted
@@ -116,16 +122,20 @@ export namespace Hovers {
 				editorLine,
 			)} "Open Changes")`;
 
-			previous = `[$(git-commit) ${commit.previousShortSha}](${ShowQuickCommitCommand.getMarkdownCommandArgs(
-				commit.previousSha,
-			)} "Show Commit")`;
+			if (commit.previousSha) {
+				previous = `  &nbsp;[$(git-commit) ${
+					commit.previousShortSha
+				}](${ShowQuickCommitCommand.getMarkdownCommandArgs(commit.previousSha)} "Show Commit") &nbsp;${
+					GlyphChars.ArrowLeftRightLong
+				}&nbsp;`;
+			}
 
 			current = `[$(git-commit) ${commit.shortSha}](${ShowQuickCommitCommand.getMarkdownCommandArgs(
 				commit.sha,
 			)} "Show Commit")`;
 		}
 
-		message = `${diff}\n---\n\nChanges  &nbsp;${previous} &nbsp;${GlyphChars.ArrowLeftRightLong}&nbsp; ${current} &nbsp;&nbsp;|&nbsp;&nbsp; ${message}`;
+		message = `${diff}\n---\n\nChanges${previous ?? ' added in '}${current} &nbsp;&nbsp;|&nbsp;&nbsp; ${message}`;
 
 		const markdown = new MarkdownString(message, true);
 		markdown.supportHtml = true;

src/hovers/lineHoverController.ts

@@ -193,7 +193,12 @@ export class LineHoverController implements Disposable {
 		const trackedDocument = await this.container.tracker.get(document);
 		if (trackedDocument == null) return undefined;
 
-		const message = await Hovers.changesMessage(commit, trackedDocument.uri, position.line);
+		const message = await Hovers.changesMessage(
+			commit,
+			trackedDocument.uri,
+			position.line,
+			trackedDocument.document,
+		);
 		if (message == null) return undefined;
 
 		return new Hover(message, range);