[PATCH 0/2] [GSoC] userdiff: adding typescript pattern

[PATCH 0/2] [GSoC] userdiff: adding typescript pattern

[Dhruv Arora via GitGitGadget]

Description
===========

 * Add builtin userdiff pattern for TypeScript files. Recognizes function
   declarations, class definitions, arrow functions, and method definitions.
   
   * Handles common modifiers like export, async, static, etc

 * Added tests for the typescript pattern in userdiff.

Dhruv Arora (2):
  userdiff: adding typescript pattern
  fix(userdiff): sorted pattern and tests

 t/t4018/typescript-class-method         |  7 +++++++
 t/t4018/typescript-export-default-class |  7 +++++++
 t/t4018/typescript-export-function      |  7 +++++++
 userdiff.c                              | 15 +++++++++++++++
 4 files changed, 36 insertions(+)
 create mode 100644 t/t4018/typescript-class-method
 create mode 100644 t/t4018/typescript-export-default-class
 create mode 100644 t/t4018/typescript-export-function


base-commit: ce74208c2fa13943fffa58f168ac27a76d0eb789
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2251%2FDhruv-0-Arora%2Fuserdiff%2Ftypescript-pattern-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2251/Dhruv-0-Arora/userdiff/typescript-pattern-v1
Pull-Request: https://github.com/git/git/pull/2251
-- 
gitgitgadget

[PATCH 1/2] userdiff: adding typescript pattern

[Dhruv Arora via GitGitGadget]

From: Dhruv Arora <a_dhruv@outlook.com>

Add builtin userdiff pattern for TypeScript files.
Recognizes function declarations, class definitions,
arrow functions, and method definitions.

Handles common modifiers like export, async, static, etc..

Signed-off-by: Dhruv Arora <a_dhruv@outlook.com>
---
 userdiff.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/userdiff.c b/userdiff.c
index fe710a68bf..086e3fa002 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -337,6 +337,19 @@ PATTERNS("ruby",
 	 "(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
 	 "|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
 	 "|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
+PATTERNS("typescript",
+	/* Starting with optional whitespace */
+	"^[ \t]*"
+	/* Followed by an optional export and/or async keyword */
+	"((export[ \t]+)?(async[ \t]+)?"
+	/* Followed by either a function or class declaration */
+	"((function|class)[ \t]+[a-zA-Z_][a-zA-Z0-9_]*[^{]*)"
+	/* or */
+	"|"
+	/* a variable declaration with const, let, or var */
+	"([ \t]*(const|let|var)[ \t]+[a-zA-Z_][a-zA-Z0-9_]*[ \t]*=))",
+	/* -- */
+	"[a-zA-Z_][a-zA-Z0-9_]*"),
 PATTERNS("rust",
 	 "^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl|macro_rules!)[< \t]+[^;]*)$",
 	 /* -- */
-- 
gitgitgadget

[PATCH 2/2] fix(userdiff): sorted pattern and tests

[Dhruv Arora via GitGitGadget]

From: Dhruv Arora <a_dhruv@outlook.com>

- Typescript pattern was not in alphabetical order, causing failing tests.
- Added 3 new typescript tests.
- Fixed pattern bug - incorrectly identifying const|let|var instead of
function or class.

Signed-off-by: Dhruv Arora <a_dhruv@outlook.com>
---
 t/t4018/typescript-class-method         |  7 +++++++
 t/t4018/typescript-export-default-class |  7 +++++++
 t/t4018/typescript-export-function      |  7 +++++++
 userdiff.c                              | 28 +++++++++++++------------
 4 files changed, 36 insertions(+), 13 deletions(-)
 create mode 100644 t/t4018/typescript-class-method
 create mode 100644 t/t4018/typescript-export-default-class
 create mode 100644 t/t4018/typescript-export-function

diff --git a/t/t4018/typescript-class-method b/t/t4018/typescript-class-method
new file mode 100644
index 0000000000..6de6eff2e7
--- /dev/null
+++ b/t/t4018/typescript-class-method
@@ -0,0 +1,7 @@
+export class RIGHT {
+    unique = 0
+    constructor () {
+        this.doNothing()
+    }
+    function ChangeMe() { }
+}
diff --git a/t/t4018/typescript-export-default-class b/t/t4018/typescript-export-default-class
new file mode 100644
index 0000000000..aaede0dce3
--- /dev/null
+++ b/t/t4018/typescript-export-default-class
@@ -0,0 +1,7 @@
+export default class RIGHT {
+	private x = 0;
+	private y = 0;
+	private z = 0;
+	// ChangeMe
+	render() {}
+}
diff --git a/t/t4018/typescript-export-function b/t/t4018/typescript-export-function
new file mode 100644
index 0000000000..ba5bf71e80
--- /dev/null
+++ b/t/t4018/typescript-export-function
@@ -0,0 +1,7 @@
+export async function RIGHT(url: string): Promise<string> {
+	const a = 1;
+	const b = 2;
+	const c = 3;
+	ChangeMe
+	return url;
+}
diff --git a/userdiff.c b/userdiff.c
index 086e3fa002..7f5cadb30b 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -337,19 +337,6 @@ PATTERNS("ruby",
 	 "(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
 	 "|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
 	 "|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
-PATTERNS("typescript",
-	/* Starting with optional whitespace */
-	"^[ \t]*"
-	/* Followed by an optional export and/or async keyword */
-	"((export[ \t]+)?(async[ \t]+)?"
-	/* Followed by either a function or class declaration */
-	"((function|class)[ \t]+[a-zA-Z_][a-zA-Z0-9_]*[^{]*)"
-	/* or */
-	"|"
-	/* a variable declaration with const, let, or var */
-	"([ \t]*(const|let|var)[ \t]+[a-zA-Z_][a-zA-Z0-9_]*[ \t]*=))",
-	/* -- */
-	"[a-zA-Z_][a-zA-Z0-9_]*"),
 PATTERNS("rust",
 	 "^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl|macro_rules!)[< \t]+[^;]*)$",
 	 /* -- */
@@ -367,6 +354,21 @@ PATTERNS("scheme",
 	 "|([^][)(}{[ \t])+"),
 PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
 	 "\\\\[a-zA-Z@]+|\\\\.|([a-zA-Z0-9]|[^\x01-\x7f])+"),
+PATTERNS("typescript",
+	/* Starting with optional whitespace */
+	"^[ \t]*"
+	"("
+	/* Followed by an optional export and/or async and/or default keyword */
+	"(export[ \t]+)?(default[ \t]+)?(async[ \t]+)?"
+	/* Followed by either a function or class declaration */
+	"((function|class)[ \t]+[a-zA-Z_][a-zA-Z0-9_]*[^{]*)"
+	/* or */
+	"|"
+	/* a variable declaration with const, let, or var */
+	"^(const|let|var)[ \\t]+[a-zA-Z_][a-zA-Z0-9_]*[ \\t]*="
+	")",
+	/* -- */
+	"[a-zA-Z_][a-zA-Z0-9_]*"),
 { .name = "default", .binary = -1 },
 };
 #undef PATTERNS
-- 
gitgitgadget

Re: [PATCH 0/2] [GSoC] userdiff: adding typescript pattern

[Junio C Hamano]

"Dhruv Arora via GitGitGadget" <gitgitgadget@gmail.com> writes:

> Description
> ===========
>
>  * Add builtin userdiff pattern for TypeScript files. Recognizes function
>    declarations, class definitions, arrow functions, and method definitions.
>    
>    * Handles common modifiers like export, async, static, etc
>
>  * Added tests for the typescript pattern in userdiff.
>
> Dhruv Arora (2):
>   userdiff: adding typescript pattern
>   fix(userdiff): sorted pattern and tests

We frown upon a patch series that makes mistakes in an earlier step,
only to fix them in a later step.  The "git rebase -i" command helps
us pretend to be more perfect developers than we actually are,
whipping your patch series into a shape that builds one small step
on top of another in a logical succession.  Such a patch series is
easier to understand than a history that faithfully records all the
stumbles the developer made until they reached the final solution.

Just have a single patch that adds the right pattern at the right
place and add necessary tests.

When/if your reviewers suggest further changes, the way you should
work on them is the same.  Pretend as if you discarded everything
you did, started from scratch, and reached the ideal result without
making any mistakes or taking any detours along the way.

Thanks.

>  t/t4018/typescript-class-method         |  7 +++++++
>  t/t4018/typescript-export-default-class |  7 +++++++
>  t/t4018/typescript-export-function      |  7 +++++++
>  userdiff.c                              | 15 +++++++++++++++
>  4 files changed, 36 insertions(+)
>  create mode 100644 t/t4018/typescript-class-method
>  create mode 100644 t/t4018/typescript-export-default-class
>  create mode 100644 t/t4018/typescript-export-function
>
>
> base-commit: ce74208c2fa13943fffa58f168ac27a76d0eb789
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2251%2FDhruv-0-Arora%2Fuserdiff%2Ftypescript-pattern-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2251/Dhruv-0-Arora/userdiff/typescript-pattern-v1
> Pull-Request: https://github.com/git/git/pull/2251

Re: [PATCH 0/2] [GSoC] userdiff: adding typescript pattern

[Johannes Sixt]

Am 28.03.26 um 22:40 schrieb Dhruv Arora via GitGitGadget:
> 
> Description
> ===========
> 
>  * Add builtin userdiff pattern for TypeScript files. Recognizes function
>    declarations, class definitions, arrow functions, and method definitions.
>    
>    * Handles common modifiers like export, async, static, etc
> 
>  * Added tests for the typescript pattern in userdiff.
> 
> Dhruv Arora (2):
>   userdiff: adding typescript pattern
>   fix(userdiff): sorted pattern and tests
> 
>  t/t4018/typescript-class-method         |  7 +++++++
>  t/t4018/typescript-export-default-class |  7 +++++++
>  t/t4018/typescript-export-function      |  7 +++++++
>  userdiff.c                              | 15 +++++++++++++++
>  4 files changed, 36 insertions(+)
>  create mode 100644 t/t4018/typescript-class-method
>  create mode 100644 t/t4018/typescript-export-default-class
>  create mode 100644 t/t4018/typescript-export-function
> 
> 
> base-commit: ce74208c2fa13943fffa58f168ac27a76d0eb789
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2251%2FDhruv-0-Arora%2Fuserdiff%2Ftypescript-pattern-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2251/Dhruv-0-Arora/userdiff/typescript-pattern-v1
> Pull-Request: https://github.com/git/git/pull/2251

Javascript and Typescript are related languages, if I am not mistaken.
It would be appreciated if the new language driver could be used for
both. Then the driver's name should be the superset language and the
documentation (missing, BTW) should mention that the driver can be used
for both languages.

We have had a number of submissions for Javascript or Typescript drivers
in the past, but none of them were followed through to be integrated.

Typescript:

https://lore.kernel.org/git/20240404163827.5855-1-utsavp0213@gmail.com/
https://lore.kernel.org/git/pull.1746.git.git.1721061218993.gitgitgadget@gmail.com/

Javascript:

https://lore.kernel.org/git/20240301074048.188835-1-sergiusnyah@gmail.com/
https://lore.kernel.org/git/20220403132508.28196-1-a97410985new@gmail.com/
https://lore.kernel.org/git/20250604094100.80598-1-derick.william.moraes@gmail.com/

Please review these submission and the responses that they received.
Perhaps you can find inspiration for improvement from them.

-- Hannes

Spelling JavaScript (was: Re: [PATCH 0/2] [GSoC] userdiff: adding typescript pattern)

[Ben Knoble]

> Le 29 mars 2026 à 05:32, Johannes Sixt <j6t@kdbg.org> a écrit :
> 
> Javascript and Typescript are related languages, if I am not mistaken.
> 
> -- Hannes

FWIW, I believe both languages are officially spelled with a capital S: “JavaScript”, “TypeScript”. At least that is how Wikipedia and official sites present them.

I knew what you meant of course, and will now take my pedant hat off ;)