[RFC PATCH v3 3/4] branch: introduce dont_fail parameter for branchname validation

From

Kaartic Sivaraam <kaartic.sivaraam@gmail.com>

Date

Nov 2, 2017, 06:54 UTC

Message-ID

<20171102065407.25404-4-kaartic.sivaraam@gmail.com>

In-Reply-To

<20171102065407.25404-1-kaartic.sivaraam@gmail.com>

Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Signed-off-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
---
 branch.c           | 62 +++++++++++++++++++++++++++++++-----------------------
 branch.h           | 60 ++++++++++++++++++++++++++++++++++++++++++----------
 builtin/branch.c   |  4 ++--
 builtin/checkout.c |  5 +++--
 4 files changed, 90 insertions(+), 41 deletions(-)

diff --git a/branch.c b/branch.c
index 7c8093041..7db2e3296 100644
--- a/branch.c
+++ b/branch.c
@@ -178,41 +178,51 @@ int read_branch_desc(struct strbuf *buf, const char *branch_name)
 	return 0;
 }
 
-/*
- * Check if 'name' can be a valid name for a branch; die otherwise.
- * Return 1 if the named branch already exists; return 0 otherwise.
- * Fill ref with the full refname for the branch.
- */
-int validate_branchname(const char *name, struct strbuf *ref)
+enum branch_validation_result validate_branchname(const char *name, struct strbuf *ref, unsigned dont_fail)
 {
-	if (strbuf_check_branch_ref(ref, name))
-		die(_("'%s' is not a valid branch name."), name);
+	if (strbuf_check_branch_ref(ref, name)) {
+		if (dont_fail)
+			return INVALID_BRANCH_NAME;
+		else
+			die(_("'%s' is not a valid branch name."), name);
+	}
 
-	return ref_exists(ref->buf);
+	if(ref_exists(ref->buf))
+		return BRANCH_EXISTS;
+	else
+		return BRANCH_DOESNT_EXIST;
 }
 
-/*
- * Check if a branch 'name' can be created as a new branch; die otherwise.
- * 'force' can be used when it is OK for the named branch already exists.
- * Return 1 if the named branch already exists; return 0 otherwise.
- * Fill ref with the full refname for the branch.
- */
-int validate_new_branchname(const char *name, struct strbuf *ref, int force)
+enum branch_validation_result validate_new_branchname(const char *name, struct strbuf *ref, int force, unsigned dont_fail)
 {
 	const char *head;
 
-	if (!validate_branchname(name, ref))
-		return 0;
+	if(dont_fail) {
+		enum branch_validation_result res = validate_branchname(name, ref, 1);
+		if (res == INVALID_BRANCH_NAME || res == BRANCH_DOESNT_EXIST)
+				return res;
+	} else {
+		if(validate_branchname(name, ref, 0) == BRANCH_DOESNT_EXIST)
+			return BRANCH_DOESNT_EXIST;
+	}
 
-	if (!force)
-		die(_("A branch named '%s' already exists."),
-		    ref->buf + strlen("refs/heads/"));
+	if (!force) {
+		if (dont_fail)
+			return BRANCH_EXISTS_NO_FORCE;
+		else
+			die(_("A branch named '%s' already exists."),
+				ref->buf + strlen("refs/heads/"));
+	}
 
 	head = resolve_ref_unsafe("HEAD", 0, NULL, NULL);
-	if (!is_bare_repository() && head && !strcmp(head, ref->buf))
-		die(_("Cannot force update the current branch."));
+	if (!is_bare_repository() && head && !strcmp(head, ref->buf)) {
+		if (dont_fail)
+			return CANNOT_FORCE_UPDATE_CURRENT_BRANCH;
+		else
+			die(_("Cannot force update the current branch."));
+	}
 
-	return 1;
+	return BRANCH_EXISTS;
 }
 
 static int check_tracking_branch(struct remote *remote, void *cb_data)
@@ -259,8 +269,8 @@ void create_branch(const char *name, const char *start_name,
 		explicit_tracking = 1;
 
 	if ((track == BRANCH_TRACK_OVERRIDE || clobber_head_ok)
-	    ? validate_branchname(name, &ref)
-	    : validate_new_branchname(name, &ref, force)) {
+	    ? validate_branchname(name, &ref, 0)
+	    : validate_new_branchname(name, &ref, force, 0)) {
 		if (!force)
 			dont_change_ref = 1;
 		else
diff --git a/branch.h b/branch.h
index 85052628b..0c178ec5a 100644
--- a/branch.h
+++ b/branch.h
@@ -27,20 +27,58 @@ void create_branch(const char *name, const char *start_name,
 		   enum branch_track track, int force, int clobber_head_ok,
 		   int reflog, int quiet);
 
-/*
- * Check if 'name' can be a valid name for a branch; die otherwise.
- * Return 1 if the named branch already exists; return 0 otherwise.
- * Fill ref with the full refname for the branch.
- */
-extern int validate_branchname(const char *name, struct strbuf *ref);
+enum branch_validation_result {
+	/* Flags that convey that validation FAILED */
+	BRANCH_EXISTS_NO_FORCE = -3,
+	CANNOT_FORCE_UPDATE_CURRENT_BRANCH,
+	INVALID_BRANCH_NAME,
+	/* Flags that convey that validation SUCCEEDED */
+	BRANCH_DOESNT_EXIST = 0,
+	BRANCH_EXISTS = 1,
+};
 
 /*
- * Check if a branch 'name' can be created as a new branch; die otherwise.
- * 'force' can be used when it is OK for the named branch already exists.
- * Return 1 if the named branch already exists; return 0 otherwise.
- * Fill ref with the full refname for the branch.
+ * Check if 'name' can be a valid name for a branch; die otherwise.
+ *
+ *   - name is the new branch name
+ *
+ *   - ref is used to return the full refname for the branch
+ *
+ * The return values have the following meaning,
+ *
+ *   - If dont_fail is 0, the function dies in case of failure and returns flags of
+ *     'branch_validation_result' that indicate status of the given branch. The positive
+ *     non-zero flag implies that the branch exists.
+ *
+ *   - If dont_fail is 1, the function doesn't die in case of failure but returns flags
+ *     of 'branch_validaton_result' that specify the reason for failure. The behaviour in case of
+ *     success is same as above.
+ *
  */
-extern int validate_new_branchname(const char *name, struct strbuf *ref, int force);
+extern enum branch_validation_result validate_branchname(const char *name, struct strbuf *ref, unsigned dont_fail);
+
+/*
+ * Check if a branch 'name' can be created as a new branch.
+ *
+ *   - name is the new branch name
+ *
+ *   - ref is used to return the full refname for the branch
+ *
+ *   - force can be used when it is OK if the named branch already exists.
+ *     the currently checkout branch; with 'shouldnt_exist', it has no effect.
+ *
+ * The return values have the following meaning,
+ *
+ *   - If dont_fail is 0, the function dies in case of failure and returns flags of
+ *     'branch_validation_result' that indicate that convey status of given branch. The positive
+ *     non-zero flag implies that the branch can be force updated.
+ *
+ *   - If dont_fail is 1, the function doesn't die in case of failure but returns flags
+ *     of 'branch_validaton_result' that specify the reason for failure. The behaviour in case of
+ *     success is same as above.
+ *
+ */
+extern enum branch_validation_result validate_new_branchname(const char *name, struct strbuf *ref, int force, unsigned dont_fail);
 
 /*
  * Remove information about the state of working on the current
diff --git a/builtin/branch.c b/builtin/branch.c
index df06ac968..7018e5d75 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -487,9 +487,9 @@ static void copy_or_rename_branch(const char *oldname, const char *newname, int
 	 * cause the worktree to become inconsistent with HEAD, so allow it.
 	 */
 	if (!strcmp(oldname, newname))
-		validate_branchname(newname, &newref);
+		validate_branchname(newname, &newref, 0);
 	else
-		validate_new_branchname(newname, &newref, force);
+		validate_new_branchname(newname, &newref, force, 0);
 
 	reject_rebase_or_bisect_branch(oldref.buf);
 
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 5c34a9a0d..4adab3814 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -1288,10 +1288,11 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 		struct strbuf buf = STRBUF_INIT;
 
 		if (opts.new_branch_force)
-			opts.branch_exists = validate_branchname(opts.new_branch, &buf);
+			opts.branch_exists = validate_branchname(opts.new_branch, &buf, 0);
 		else
 			opts.branch_exists =
-				validate_new_branchname(opts.new_branch, &buf, 0);
+				validate_new_branchname(opts.new_branch, &buf, 0, 0);
+
 		strbuf_release(&buf);
 	}
 

-- 
2.15.0.461.gf957c703b.dirty