test: more TDD coverage + version 0.5.27

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "diffscope"
-version = "0.5.26"
+version = "0.5.27"
 edition = "2021"
 rust-version = "1.88"
 authors = ["Jonathan Haas <jonathan@haas.holdings>"]

src/config.rs

@@ -2184,6 +2184,25 @@ triage_skip_deletion_only: true
         assert!(config.triage_skip_deletion_only);
     }
 
+    #[test]
+    fn test_config_default_triage_skip_deletion_only_false() {
+        let config = Config::default();
+        assert!(
+            !config.triage_skip_deletion_only,
+            "default: deletions get review unless explicitly enabled"
+        );
+    }
+
+    #[test]
+    fn test_config_deserialize_triage_skip_deletion_only_false() {
+        let yaml = r#"
+model: claude-sonnet-4-6
+triage_skip_deletion_only: false
+"#;
+        let config: Config = serde_yaml::from_str(yaml).unwrap();
+        assert!(!config.triage_skip_deletion_only);
+    }
+
     #[test]
     fn test_default_frontier_role_models_match_requested_pair() {
         let config = Config::default();

src/parsing/llm_response.rs

@@ -436,28 +436,32 @@ fn convert_single_quoted_json_to_double(s: &str) -> String {
         }
         if c == '\'' {
             // Start of single-quoted string: emit " and copy until unescaped ', escaping " and \.
+            // Inside single-quoted: \' → one quote in JSON (emit \"); \\ → emit \\; \" → emit \"
             out.push('"');
+            let mut single_escape = false;
             for c in chars.by_ref() {
-                if c == '\\' {
-                    escape_next = true;
-                    out.push(c);
-                } else if c == '\'' {
-                    if escape_next {
-                        escape_next = false;
-                        out.push('\'');
+                if single_escape {
+                    single_escape = false;
+                    if c == '\'' {
+                        out.push('\''); // apostrophe in JSON string needs no escape
                     } else {
-                        out.push('"');
-                        break;
+                        out.push('\\');
+                        out.push(c);
                     }
+                } else if c == '\\' {
+                    single_escape = true;
+                } else if c == '\'' {
+                    out.push('"');
+                    break;
                 } else if c == '"' {
                     out.push('\\');
                     out.push('"');
                 } else {
                     out.push(c);
                 }
             }
-            if escape_next {
-                escape_next = false;
+            if single_escape {
+                out.push('\\');
             }
             continue;
         }
@@ -1349,6 +1353,43 @@ let data = &input;
         assert!(comments[0].content.contains("deprecated"));
     }
 
+    #[test]
+    fn parse_json_single_quoted_object_wrapped_in_findings() {
+        // Outer object with "findings" key; inner array uses single quotes — raw bracket span + repair.
+        let input = r#"{"findings": [{'line': 2, 'issue': 'Minor bug'}]}"#;
+        let file_path = PathBuf::from("src/lib.rs");
+        let comments = parse_llm_response(input, &file_path).unwrap();
+        assert_eq!(comments.len(), 1);
+        assert_eq!(comments[0].line_number, 2);
+        assert!(comments[0].content.contains("Minor bug"));
+    }
+
+    #[test]
+    fn parse_json_single_quoted_value_with_escaped_apostrophe() {
+        // Single-quoted value containing escaped apostrophe (e.g. "don't") — converter preserves it.
+        let input = r#"[{'line': 1, 'issue': 'don\'t forget'}]"#;
+        let file_path = PathBuf::from("src/lib.rs");
+        let comments = parse_llm_response(input, &file_path).unwrap();
+        assert_eq!(comments.len(), 1);
+        assert_eq!(comments[0].line_number, 1);
+        assert!(
+            comments[0].content.contains("don't"),
+            "content should contain apostrophe: {:?}",
+            comments[0].content
+        );
+    }
+
+    #[test]
+    fn parse_json_double_quoted_value_with_apostrophe_unchanged() {
+        // Valid JSON with apostrophe in double-quoted string — no repair; parses as-is.
+        let input = r#"[{"line": 3, "issue": "don't use deprecated API"}]"#;
+        let file_path = PathBuf::from("src/lib.rs");
+        let comments = parse_llm_response(input, &file_path).unwrap();
+        assert_eq!(comments.len(), 1);
+        assert_eq!(comments[0].line_number, 3);
+        assert!(comments[0].content.contains("don't"));
+    }
+
     // ── Bug: find_json_array uses mismatched brackets ──────────────────
     //
     // `find_json_array` uses `find('[')` (first) + `rfind(']')` (last).

src/review/pipeline/guidance.rs

@@ -115,4 +115,53 @@ mod tests {
         assert!(guidance.contains("Always use parameterized queries"));
         assert!(guidance.contains("No direct SQL string concatenation"));
     }
+
+    #[test]
+    fn build_review_guidance_no_prose_section_when_rules_none() {
+        let config = config::Config {
+            review_rules_prose: None,
+            ..config::Config::default()
+        };
+        let guidance = build_review_guidance(&config, None).unwrap();
+        assert!(
+            !guidance.contains("Custom rules (natural language)"),
+            "guidance should not include prose section when review_rules_prose is None"
+        );
+    }
+
+    #[test]
+    fn build_review_guidance_no_prose_section_when_rules_empty() {
+        let config = config::Config {
+            review_rules_prose: Some(vec![]),
+            ..config::Config::default()
+        };
+        let guidance = build_review_guidance(&config, None).unwrap();
+        assert!(
+            !guidance.contains("Custom rules (natural language)"),
+            "guidance should not include prose section when review_rules_prose is empty"
+        );
+    }
+
+    #[test]
+    fn build_review_guidance_single_prose_rule() {
+        let config = config::Config {
+            review_rules_prose: Some(vec!["Single rule.".to_string()]),
+            ..config::Config::default()
+        };
+        let guidance = build_review_guidance(&config, None).unwrap();
+        assert!(guidance.contains("Custom rules (natural language)"));
+        assert!(guidance.contains("Single rule."));
+    }
+
+    #[test]
+    fn build_review_guidance_prose_rule_with_special_chars() {
+        let config = config::Config {
+            review_rules_prose: Some(vec!["Check for <script> injection in HTML.".to_string()]),
+            ..config::Config::default()
+        };
+        let guidance = build_review_guidance(&config, None).unwrap();
+        assert!(guidance.contains("Custom rules (natural language)"));
+        assert!(guidance.contains("<script>"));
+        assert!(guidance.contains("injection"));
+    }
 }

src/review/triage.rs

@@ -695,6 +695,25 @@ mod tests {
         );
     }
 
+    // ── TriageOptions and reason strings ───────────────────────────────────
+
+    #[test]
+    fn test_triage_options_default_skip_deletion_only_false() {
+        let options = TriageOptions::default();
+        assert!(
+            !options.skip_deletion_only,
+            "default should not skip deletion-only so deletions still get review"
+        );
+    }
+
+    #[test]
+    fn test_reason_skip_deletion_only_exact() {
+        assert_eq!(
+            TriageResult::SkipDeletionOnly.reason(),
+            "deletion-only changes"
+        );
+    }
+
     // ── #29 optional skip deletion-only ──────────────────────────────────
 
     #[test]