Merge branch 'jk/fix-alias-pager-config-key-warnings' into maint

Because the configuration system does not allow "alias.0foo" and
"pager.0foo" as the configuration key, the user cannot use '0foo'
as a custom command name anyway, but "git 0foo" tried to look these
keys up and emitted useless warnings before saying '0foo is not a
git command'.  These warning messages have been squelched.

* jk/fix-alias-pager-config-key-warnings:
  config: silence warnings for command names with invalid keys

alias.c

@@ -5,7 +5,8 @@ char *alias_lookup(const char *alias)
 	char *v = NULL;
 	struct strbuf key = STRBUF_INIT;
 	strbuf_addf(&key, "alias.%s", alias);
-	git_config_get_string(key.buf, &v);
+	if (git_config_key_is_valid(key.buf))
+		git_config_get_string(key.buf, &v);
 	strbuf_release(&key);
 	return v;
 }

cache.h

@@ -1446,6 +1446,7 @@ extern int git_config_pathname(const char **, const char *, const char *);
 extern int git_config_set_in_file(const char *, const char *, const char *);
 extern int git_config_set(const char *, const char *);
 extern int git_config_parse_key(const char *, char **, int *);
+extern int git_config_key_is_valid(const char *key);
 extern int git_config_set_multivar(const char *, const char *, const char *, int);
 extern int git_config_set_multivar_in_file(const char *, const char *, const char *, const char *, int);
 extern int git_config_rename_section(const char *, const char *);

config.c

@@ -1848,7 +1848,7 @@ int git_config_set(const char *key, const char *value)
  * baselen - pointer to int which will hold the length of the
  *           section + subsection part, can be NULL
  */
-int git_config_parse_key(const char *key, char **store_key, int *baselen_)
+static int git_config_parse_key_1(const char *key, char **store_key, int *baselen_, int quiet)
 {
 	int i, dot, baselen;
 	const char *last_dot = strrchr(key, '.');
@@ -1859,12 +1859,14 @@ int git_config_parse_key(const char *key, char **store_key, int *baselen_)
 	 */
 
 	if (last_dot == NULL || last_dot == key) {
-		error("key does not contain a section: %s", key);
+		if (!quiet)
+			error("key does not contain a section: %s", key);
 		return -CONFIG_NO_SECTION_OR_NAME;
 	}
 
 	if (!last_dot[1]) {
-		error("key does not contain variable name: %s", key);
+		if (!quiet)
+			error("key does not contain variable name: %s", key);
 		return -CONFIG_NO_SECTION_OR_NAME;
 	}
 
@@ -1875,7 +1877,8 @@ int git_config_parse_key(const char *key, char **store_key, int *baselen_)
 	/*
 	 * Validate the key and while at it, lower case it for matching.
 	 */
-	*store_key = xmalloc(strlen(key) + 1);
+	if (store_key)
+		*store_key = xmalloc(strlen(key) + 1);
 
 	dot = 0;
 	for (i = 0; key[i]; i++) {
@@ -1886,26 +1889,42 @@ int git_config_parse_key(const char *key, char **store_key, int *baselen_)
 		if (!dot || i > baselen) {
 			if (!iskeychar(c) ||
 			    (i == baselen + 1 && !isalpha(c))) {
-				error("invalid key: %s", key);
+				if (!quiet)
+					error("invalid key: %s", key);
 				goto out_free_ret_1;
 			}
 			c = tolower(c);
 		} else if (c == '\n') {
-			error("invalid key (newline): %s", key);
+			if (!quiet)
+				error("invalid key (newline): %s", key);
 			goto out_free_ret_1;
 		}
-		(*store_key)[i] = c;
+		if (store_key)
+			(*store_key)[i] = c;
 	}
-	(*store_key)[i] = 0;
+	if (store_key)
+		(*store_key)[i] = 0;
 
 	return 0;
 
 out_free_ret_1:
-	free(*store_key);
+	if (store_key) {
-	*store_key = NULL;
+		free(*store_key);
+		*store_key = NULL;
+	}
 	return -CONFIG_INVALID_KEY;
 }
 
+int git_config_parse_key(const char *key, char **store_key, int *baselen)
+{
+	return git_config_parse_key_1(key, store_key, baselen, 0);
+}
+
+int git_config_key_is_valid(const char *key)
+{
+	return !git_config_parse_key_1(key, NULL, NULL, 1);
+}
+
 /*
  * If value==NULL, unset in (remove from) config,
  * if value_regex!=NULL, disregard key/value pairs where value does not match.

pager.c

@@ -150,7 +150,8 @@ int check_pager_config(const char *cmd)
 	struct strbuf key = STRBUF_INIT;
 	const char *value = NULL;
 	strbuf_addf(&key, "pager.%s", cmd);
-	if (!git_config_get_value(key.buf, &value)) {
+	if (git_config_key_is_valid(key.buf) &&
+	    !git_config_get_value(key.buf, &value)) {
 		int b = git_config_maybe_bool(key.buf, value);
 		if (b >= 0)
 			want = b;

t/t7006-pager.sh

@@ -447,4 +447,13 @@ test_expect_success TTY 'external command pagers override sub-commands' '
 	test_cmp expect actual
 '
 
+test_expect_success 'command with underscores does not complain' '
+	write_script git-under_score <<-\EOF &&
+	echo ok
+	EOF
+	git --exec-path=. under_score >actual 2>&1 &&
+	echo ok >expect &&
+	test_cmp expect actual
+'
+
 test_done