Subject: [PATCH v5 0/3] Advice on checkout dirty files

From: "Arsh Srivastava via GitGitGadget" <[email-masked]>
Date: Wed, 11 Mar 2026 17:49:26 +0000

This is my submission for microproject [GSOC]

This patch adds a new advice type ADVICE_STASH_BEFORE_CHECKOUT to help users
when they attempt to switch branches with local modifications that would be
overwritten by the operation.

The new advice follows the same patterns established by existing advice
functions such as advise_on_updating_sparse_paths(). When triggered, it
lists the affected files and suggests using git stash push/pop to save and
restore local changes.

The advice can be silenced with:

git config set advice.stashBeforeCheckout false

Changes:

> advice.h: add ADVICE_STASH_BEFORE_CHECKOUT enum value advice.c: add
> "stashBeforeCheckout" to advice_setting[] and implement
> advise_on_checkout_dirty_files() function
> Documentation/config/advice.adoc: document the new advice key

Signed-off-by: Arsh Srivastava [email-masked]

Arsh Srivastava (3):
  advice: add stashBeforeCheckout advice for dirty branch switches
  advice: add stashBeforeCheckout advice for dirty branch switches
    [GSOC]
  unpack-trees: suggesting 'git checkout -m <branch>' with its
    repercussions

 t/t6439-merge-co-error-msgs.sh | 6 ++++++
 t/t7406-submodule-update.sh    | 3 +++
 unpack-trees.c                 | 9 +++++++--
 3 files changed, 16 insertions(+), 2 deletions(-)

base-commit: d181b9354cf85b44455ce3ca9e6af0b9559e0ae2
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2233%2FArsh123344423%2Fadvice_on_checkout_dirty_files-v5
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2233/Arsh123344423/advice_on_checkout_dirty_files-v5
Pull-Request: https://github.com/git/git/pull/2233

Range-diff vs v4:

 1:  eb5639dbc3 = 1:  eb5639dbc3 advice: add stashBeforeCheckout advice for dirty branch switches
 2:  e88c851701 = 2:  e88c851701 advice: add stashBeforeCheckout advice for dirty branch switches [GSOC]
 3:  4237b9667d ! 3:  1cc22f437e unpack-trees: suggesting 'git checkout -m <branch>' with its repercussions
     @@ advice.h: void NORETURN die_ff_impossible(void);
       
       #endif /* ADVICE_H */
      
     + ## t/t6439-merge-co-error-msgs.sh ##
     +@@ t/t6439-merge-co-error-msgs.sh: error: Your local changes to the following files would be overwritten by checkou
     + 	rep/one
     + 	rep/two
     + Please commit your changes or stash them before you switch branches.
     ++Try using 'git checkout -m <branch>' for a quick fix.
     ++Please Note :- that using -m (merge) will not save your changes, rather would directly merge them.
     ++Meaning if you are not able to resolve conflicts and does --hard reset your local changes would be gone.
     + Aborting
     + EOF
     + 
     +@@ t/t6439-merge-co-error-msgs.sh: error: Your local changes to the following files would be overwritten by checkou
     + 	rep/one
     + 	rep/two
     + Please commit your changes or stash them before you switch branches.
     ++Try using 'git checkout -m <branch>' for a quick fix.
     ++Please Note :- that using -m (merge) will not save your changes, rather would directly merge them.
     ++Meaning if you are not able to resolve conflicts and does --hard reset your local changes would be gone.
     + Aborting
     + EOF
     + 
     +
     + ## t/t7406-submodule-update.sh ##
     +@@ t/t7406-submodule-update.sh: test_expect_success 'submodule update should fail due to local changes' '
     + 	> error: Your local changes to the following files would be overwritten by checkout:
     + 	> 	file
     + 	> Please commit your changes or stash them before you switch branches.
     ++	> Try using '\''git checkout -m <branch>'\'' for a quick fix.
     ++	> Please Note :- that using -m (merge) will not save your changes, rather would directly merge them.
     ++	> Meaning if you are not able to resolve conflicts and does --hard reset your local changes would be gone.
     + 	> Aborting
     + 	> fatal: Unable to checkout OID in submodule path '\''submodule'\''
     + 	EOF
     +
       ## unpack-trees.c ##
      @@ unpack-trees.c: void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
       	if (!strcmp(cmd, "checkout"))
     @@ unpack-trees.c: void setup_unpack_trees_porcelain(struct unpack_trees_options *o
      -			  "Please commit your changes or stash them before you switch branches.")
      -		      : _("Your local changes to the following files would be overwritten by checkout:\n%%s");
      +			  "Please commit your changes or stash them before you switch branches.\n"
     -+			  "Try using 'git checkout -m <branch>' for a quick fix. \n"
     ++			  "Try using 'git checkout -m <branch>' for a quick fix.\n"
      +			  "Please Note :- that using -m (merge) will not save your changes, rather would directly merge them.\n"
      +			  "Meaning if you are not able to resolve conflicts and does --hard reset your local changes would be gone."
      +			  )
      +		      : _("Your local changes to the following files would be overwritten by checkout:\n%%s"
     -+				"Please commit your changes or stash them before you switch branches.\n"
     -+			  "Try using 'git checkout -m <branch>' for a quick fix.\n"
     -+			  "Please Note :- that using -m (merge) will not save your changes, rather would directly merge them.\n"
     -+			  "Meaning if you are not able to resolve conflicts and does --hard reset your local changes would be gone."
     -+			  );
     ++				"Please commit your changes or stash them before you switch branches.");
       	else if (!strcmp(cmd, "merge"))
       		msg = advice_enabled(ADVICE_COMMIT_BEFORE_MERGE)
       		      ? _("Your local changes to the following files would be overwritten by merge:\n%%s"
 4:  b25ea22410 < -:  ---------- Updating tests and unpack-tress.c [GSOC]
 5:  2ef7d5a3d6 < -:  ---------- File updation [GSOC]

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