Use standard git diff output even when diff.external is configured by marvin-bitterlich · Pull Request #1092 · pingdotgg/t3code

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

marvin-bitterlich · 2026-03-14T21:09:10Z

Why?

T3 Code uses git diff output to build patch and stat views in the app. When a user has diff.external configured, those commands can return tool-specific output instead of standard unified diffs, which breaks parsing and rendering.

How?

Added a small shared helper for machine-readable git diff invocations and used it for the server-side diff, stat, and numstat calls that feed status details, commit context, range context, and checkpoint diffs.

Added regression tests that configure diff.external and verify the app still receives standard diff output.

Decisions

Applied --no-ext-diff only to diff commands where T3 Code expects machine-readable output.
ClosesExternal diff tool breaks diff display #927

Note

Add `--no-ext-diff` to all git diff invocations to ignore configured external diff tools

Introduces machineReadableGitDiffArgs helper in diffArgs.ts that prepends "diff" and "--no-ext-diff" to any provided git diff arguments.
Updates GitCore (statusDetails, prepareCommitContext, readRangeContext) and CheckpointStore (diffCheckpoints) to use this helper, ensuring diff.external config is ignored.
Adds integration tests in GitCore.test.ts that configure an external diff script and assert it is not invoked by prepareCommitContext or readRangeContext.

^{Macroscope summarized 115cf97.}

coderabbitai · 2026-03-14T21:09:20Z

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 779b3522-f109-416f-a1e2-bcad1e5e1009

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📝 Coding Plan

Generate coding plan for human review comments

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can enforce grammar and style rules using `languagetool`.

Configure the reviews.tools.languagetool setting to enable/disable rules and categories. Refer to the LanguageTool Community to learn more.

Noojuno · 2026-03-14T23:58:55Z

@@ -0,0 +1,3 @@
+export function machineReadableGitDiffArgs(...args: ReadonlyArray<string>): ReadonlyArray<string> {


I don't think this helper really provides value since it increases the overall complexity by making you need to go to a different file to figure out what we're actually calling
imo you should just add the --no-ext-diff flag to the existing diff command call sites rather than trying to decrease duplication with a helper

fix(git): disable external diff tools for app diffs
115cf97

github-actionsBot added size:L 100-499 changed lines (additions + deletions). vouch:unvouched PR author is not yet trusted in the VOUCHED list. labels Mar 14, 2026

Noojuno reviewed Mar 14, 2026
View reviewed changes

marvin-bitterlich closed this Mar 30, 2026

marvin-bitterlich deleted the fix/git-diff-no-ext-diff branch March 30, 2026 21:05