fix: clarify unsupported --json field selection (#68)

Author: hex2dec

src/cli.rs

@@ -437,6 +437,7 @@ fn parse_issue_comment_args(
 ) -> Result<ParseOutcome<IssueCommentRequest>, CommandError> {
     map_parsed(parse_matches(issue_comment_command(), args), |matches| {
         let output = output_format(&matches);
+        validate_json_field_selection(&output, "issue comment", &[])?;
         let repo = last_value(&matches, "repo");
         let body_values = values(&matches, "body");
         let body_file_values = values(&matches, "body_file");
@@ -488,6 +489,7 @@ fn parse_issue_create_args(
 ) -> Result<ParseOutcome<IssueCreateRequest>, CommandError> {
     map_parsed(parse_matches(issue_create_command(), args), |matches| {
         let output = output_format(&matches);
+        validate_json_field_selection(&output, "issue create", &[])?;
         let repo = last_value(&matches, "repo");
         let title = last_value(&matches, "title");
         let body_values = values(&matches, "body");
@@ -986,24 +988,35 @@ fn flag_count(matches: &ArgMatches, id: &str) -> usize {
 }
 
 fn render_help(mut command: Command) -> CommandOutcome {
+    let supports_json_field_selection = help_command_supports_json_field_selection(&command);
     let mut buffer = Vec::new();
     command
         .write_long_help(&mut buffer)
         .expect("writing clap help should succeed");
 
-    CommandOutcome::text(
-        EXIT_OK,
-        String::from_utf8(buffer)
-            .expect("clap help should be utf-8")
-            .trim_end()
-            .to_string(),
-    )
+    let body = String::from_utf8(buffer)
+        .expect("clap help should be utf-8")
+        .trim_end()
+        .to_string();
+    let body = if supports_json_field_selection {
+        body
+    } else {
+        body.replace("--json [<FIELDS>]", "--json")
+    };
+
+    CommandOutcome::text(EXIT_OK, body)
 }
 
 fn render_version() -> CommandOutcome {
     CommandOutcome::text(EXIT_OK, format!("gitee {}", env!("CARGO_PKG_VERSION")))
 }
 
+fn help_command_supports_json_field_selection(command: &Command) -> bool {
+    let path = command.get_bin_name().unwrap_or(command.get_name());
+    let path = path.strip_prefix("gitee ").unwrap_or(path);
+    json_field_selection_for_help(path).is_some()
+}
+
 fn is_help_flag(arg: &str) -> bool {
     matches!(arg, "--help" | "-h")
 }

tests/help_cli.rs

@@ -68,6 +68,41 @@ fn help_can_render_text_for_a_nested_command_topic() {
     assert!(stdout.contains("--title <TITLE>"));
 }
 
+#[test]
+fn help_text_describes_json_usage_per_command() {
+    let pr_list_output = Command::cargo_bin("gitee")
+        .unwrap()
+        .args(["help", "pr", "list"])
+        .output()
+        .unwrap();
+
+    assert_eq!(pr_list_output.status.code(), Some(0));
+    assert!(pr_list_output.stderr.is_empty());
+    let pr_list_stdout = String::from_utf8_lossy(&pr_list_output.stdout);
+    assert!(pr_list_stdout.contains("--json [<FIELDS>]"));
+
+    for topic in [
+        ["help", "issue", "create"],
+        ["help", "issue", "comment"],
+        ["help", "pr", "comment"],
+        ["help", "pr", "checkout"],
+        ["help", "repo", "clone"],
+    ] {
+        let output = Command::cargo_bin("gitee")
+            .unwrap()
+            .args(topic)
+            .output()
+            .unwrap();
+
+        assert_eq!(output.status.code(), Some(0));
+        assert!(output.stderr.is_empty());
+
+        let stdout = String::from_utf8_lossy(&output.stdout);
+        assert!(stdout.contains("--json"));
+        assert!(!stdout.contains("--json [<FIELDS>]"));
+    }
+}
+
 #[test]
 fn help_json_can_describe_a_single_nested_command() {
     let output = Command::cargo_bin("gitee")

tests/issue_cli.rs

@@ -269,6 +269,31 @@ fn issue_create_uses_local_repo_context_and_reports_stable_json_output() {
     create_mock.assert_hits(1);
 }
 
+#[test]
+fn issue_create_rejects_json_field_selection_with_a_specific_usage_error() {
+    let output = Command::cargo_bin("gitee")
+        .unwrap()
+        .args([
+            "issue",
+            "create",
+            "--repo",
+            "octo/demo",
+            "--title",
+            "Add issue create",
+            "--json",
+            "number",
+        ])
+        .output()
+        .unwrap();
+
+    assert_eq!(output.status.code(), Some(2));
+    assert!(output.stdout.is_empty());
+    assert_eq!(
+        String::from_utf8_lossy(&output.stderr).trim(),
+        "issue create does not support selecting JSON fields yet"
+    );
+}
+
 #[test]
 fn issue_create_uses_explicit_repo_and_renders_text_output() {
     let server = MockServer::start();
@@ -980,6 +1005,32 @@ fn issue_comment_rejects_removed_body_stdin_flag_as_unsupported() {
     );
 }
 
+#[test]
+fn issue_comment_rejects_json_field_selection_with_a_specific_usage_error() {
+    let output = Command::cargo_bin("gitee")
+        .unwrap()
+        .args([
+            "issue",
+            "comment",
+            "I123",
+            "--repo",
+            "octo/demo",
+            "--body",
+            "Posted from flag",
+            "--json",
+            "number",
+        ])
+        .output()
+        .unwrap();
+
+    assert_eq!(output.status.code(), Some(2));
+    assert!(output.stdout.is_empty());
+    assert_eq!(
+        String::from_utf8_lossy(&output.stderr).trim(),
+        "issue comment does not support selecting JSON fields yet"
+    );
+}
+
 #[test]
 fn issue_comment_rejects_whitespace_only_flag_body() {
     let server = MockServer::start();