settings: simply forward .get_<type>(key) to .get::<type>(key)

There's a subtle difference in error message, but the conversion function to be
called is the same. The error message now includes "for key <key>", which is
nice.

cli/tests/test_global_opts.rs

@@ -592,6 +592,23 @@ fn test_invalid_config() {
     "###);
 }
 
+#[test]
+fn test_invalid_config_value() {
+    // Test that we get a reasonable error if a config value is invalid
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "repo"]);
+    let repo_path = test_env.env_root().join("repo");
+
+    let stderr = test_env.jj_cmd_failure(
+        &repo_path,
+        &["status", "--config-toml=snapshot.auto-track=[0]"],
+    );
+    insta::assert_snapshot!(stderr, @r"
+    Config error: invalid type: sequence, expected a string for key `snapshot.auto-track`
+    For help, see https://martinvonz.github.io/jj/latest/config/.
+    ");
+}
+
 #[test]
 fn test_no_user_configured() {
     // Test that the user is reminded if they haven't configured their name or email

lib/src/settings.rs

@@ -265,17 +265,17 @@ impl UserSettings {
 
     /// Looks up string value by `key`.
     pub fn get_string(&self, key: &str) -> Result<String, ConfigError> {
-        self.get(key).and_then(config::Value::into_string)
+        self.get(key)
     }
 
     /// Looks up integer value by `key`.
     pub fn get_int(&self, key: &str) -> Result<i64, ConfigError> {
-        self.get(key).and_then(config::Value::into_int)
+        self.get(key)
     }
 
     /// Looks up boolean value by `key`.
     pub fn get_bool(&self, key: &str) -> Result<bool, ConfigError> {
-        self.get(key).and_then(config::Value::into_bool)
+        self.get(key)
     }
 }