[PATCH v2 16/19] pull: configure --rebase via branch.<name>.rebase or pull.rebase

[Paul Tan <pyokagan@gmail.com>]

Since cd67e4d (Teach 'git pull' about --rebase, 2007-11-28),
fetch+rebase could be set by default by defining the config variable
branch.<name>.rebase. This setting can be overriden on the command line
by --rebase and --no-rebase.

Since 6b37dff (pull: introduce a pull.rebase option to enable --rebase,
2011-11-06), git-pull --rebase can also be configured via the
pull.rebase configuration option.

Re-implement support for these two configuration settings by introducing
config_get_rebase() which is called before parse_options() to set the
default value of opt_rebase.

Helped-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Paul Tan <pyokagan@gmail.com>
---

Notes:
    v2
    
    * Previously, config_get_rebase() attempted to do too many things. It:
    
      1. Checked if there was a configuration for
         branch.$curr_branch.rebase, and if not, then pull.rebase
    
      2. Parsed the configuration value and died if the value is invalid.
    
      These 2 functions have been split into config_get_rebase_default() and
      config_get_rebase() respectively.

 builtin/pull.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/builtin/pull.c b/builtin/pull.c
index 7645937..9759720 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c
@@ -258,6 +258,52 @@ static void config_get_ff(struct strbuf *sb)
 }
 
 /**
+ * Sets `value` to the REBASE_* value for the configuration setting `key`.
+ * Returns 0 is `key` exists, -1 if it does not. Dies if the value of `key` is
+ * invalid.
+ */
+static int config_get_rebase(const char *key, enum rebase_type *value)
+{
+	const char *str_value;
+
+	if (git_config_get_value(key, &str_value))
+		return -1;
+	*value = parse_config_rebase(str_value);
+	if (*value == REBASE_INVALID)
+		die(_("Invalid value for %s: %s"), key, str_value);
+	return 0;
+}
+
+/**
+ * Returns the default configured value for --rebase. It first looks for the
+ * value of "branch.$curr_branch.rebase", where $curr_branch is the current
+ * branch, and if HEAD is detached or the configuration key does not exist,
+ * looks for the value of "pull.rebase". If both configuration keys do not
+ * exist, returns REBASE_FALSE.
+ */
+static enum rebase_type config_get_rebase_default(void)
+{
+	struct branch *curr_branch = branch_get("HEAD");
+	enum rebase_type rebase_type;
+
+	if (curr_branch) {
+		int ret;
+		struct strbuf sb = STRBUF_INIT;
+
+		strbuf_addf(&sb, "branch.%s.rebase", curr_branch->name);
+		ret = config_get_rebase(sb.buf, &rebase_type);
+		strbuf_release(&sb);
+		if (!ret)
+			return rebase_type;
+	}
+
+	if (!config_get_rebase("pull.rebase", &rebase_type))
+		return rebase_type;
+
+	return REBASE_FALSE;
+}
+
+/**
  * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
  * into merge_heads.
  */
@@ -691,6 +737,8 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
 	if (!getenv("GIT_REFLOG_ACTION"))
 		set_reflog_message(argc, argv);
 
+	opt_rebase = config_get_rebase_default();
+
 	argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
 
 	parse_repo_refspecs(argc, argv, &repo, &refspecs);
-- 
2.1.4