story-kit: done 225_story_surface_merge_conflicts_and_failures_in_the_web_ui

server/src/io/fs.rs

@@ -100,7 +100,7 @@ const STORY_KIT_CLAUDE_SETTINGS: &str = r#"{
 }
 "#;
 
-const DEFAULT_PROJECT_TOML: &str = r#"[[agent]]
+const DEFAULT_PROJECT_AGENTS_TOML: &str = r#"[[agent]]
 name = "coder-1"
 stage = "coder"
 role = "Full-stack engineer. Implements features across all components."
@@ -131,6 +131,96 @@ prompt = "You are the mergemaster agent for story {{story_id}}. Call merge_agent
 system_prompt = "You are the mergemaster agent. Trigger merge_agent_work via MCP and report results. Never manually move story files. Call report_merge_failure when merges fail."
 "#;
 
+/// Detect the tech stack from the project root and return TOML `[[component]]` entries.
+///
+/// Inspects well-known marker files at the project root to identify which
+/// tech stacks are present, then emits one `[[component]]` entry per detected
+/// stack with sensible default `setup` commands. If no markers are found, a
+/// single fallback `app` component with an empty `setup` list is returned so
+/// that the pipeline never breaks on an unknown stack.
+pub fn detect_components_toml(root: &Path) -> String {
+    let mut sections = Vec::new();
+
+    if root.join("Cargo.toml").exists() {
+        sections.push(
+            "[[component]]\nname = \"server\"\npath = \".\"\nsetup = [\"cargo check\"]\n"
+                .to_string(),
+        );
+    }
+
+    if root.join("package.json").exists() {
+        let setup_cmd = if root.join("pnpm-lock.yaml").exists() {
+            "pnpm install"
+        } else {
+            "npm install"
+        };
+        sections.push(format!(
+            "[[component]]\nname = \"frontend\"\npath = \".\"\nsetup = [\"{setup_cmd}\"]\n"
+        ));
+    }
+
+    if root.join("pyproject.toml").exists() || root.join("requirements.txt").exists() {
+        sections.push(
+            "[[component]]\nname = \"python\"\npath = \".\"\nsetup = [\"pip install -r requirements.txt\"]\n"
+                .to_string(),
+        );
+    }
+
+    if root.join("go.mod").exists() {
+        sections.push(
+            "[[component]]\nname = \"go\"\npath = \".\"\nsetup = [\"go build ./...\"]\n"
+                .to_string(),
+        );
+    }
+
+    if root.join("Gemfile").exists() {
+        sections.push(
+            "[[component]]\nname = \"ruby\"\npath = \".\"\nsetup = [\"bundle install\"]\n"
+                .to_string(),
+        );
+    }
+
+    if sections.is_empty() {
+        // No tech stack markers detected — emit two example components so that
+        // the scaffold is immediately usable and agents can see the expected
+        // format.  The ONBOARDING_PROMPT instructs the chat agent to inspect
+        // the project and replace these placeholders with real definitions.
+        sections.push(
+            "# EXAMPLE: Replace with your actual backend component.\n\
+             # Common patterns: \"cargo check\" (Rust), \"go build ./...\" (Go),\n\
+             #                  \"python -m pytest\" (Python), \"mvn verify\" (Java)\n\
+             [[component]]\n\
+             name = \"backend\"\n\
+             path = \".\"\n\
+             setup = [\"cargo check\"]\n\
+             teardown = []\n"
+                .to_string(),
+        );
+        sections.push(
+            "# EXAMPLE: Replace with your actual frontend component.\n\
+             # Common patterns: \"pnpm install\" (pnpm), \"npm install\" (npm),\n\
+             #                  \"yarn\" (Yarn), \"bun install\" (Bun)\n\
+             [[component]]\n\
+             name = \"frontend\"\n\
+             path = \".\"\n\
+             setup = [\"pnpm install\"]\n\
+             teardown = []\n"
+                .to_string(),
+        );
+    }
+
+    sections.join("\n")
+}
+
+/// Generate a complete `project.toml` for a new project at `root`.
+///
+/// Detects the tech stack via [`detect_components_toml`] and prepends the
+/// resulting `[[component]]` entries before the default `[[agent]]` sections.
+fn generate_project_toml(root: &Path) -> String {
+    let components = detect_components_toml(root);
+    format!("{components}\n{DEFAULT_PROJECT_AGENTS_TOML}")
+}
+
 /// Resolve a path argument supplied on the CLI against the given working
 /// directory.  Relative paths (including `.`) are joined with `cwd` and
 /// then canonicalized when possible.  Absolute paths are returned
@@ -297,7 +387,8 @@ fn scaffold_story_kit(root: &Path) -> Result<(), String> {
         .map_err(|e| format!("Failed to create script/ directory: {}", e))?;
 
     write_file_if_missing(&story_kit_root.join("README.md"), STORY_KIT_README)?;
-    write_file_if_missing(&story_kit_root.join("project.toml"), DEFAULT_PROJECT_TOML)?;
+    let project_toml_content = generate_project_toml(root);
+    write_file_if_missing(&story_kit_root.join("project.toml"), &project_toml_content)?;
     write_file_if_missing(&specs_root.join("00_CONTEXT.md"), STORY_KIT_CONTEXT)?;
     write_file_if_missing(&tech_root.join("STACK.md"), STORY_KIT_STACK)?;
     write_script_if_missing(&script_root.join("test"), STORY_KIT_SCRIPT_TEST)?;
@@ -1254,4 +1345,194 @@ mod tests {
         // Path doesn't exist yet — canonicalize fails, fallback is cwd/newproject
         assert_eq!(result, cwd.join("newproject"));
     }
+
+    // --- detect_components_toml ---
+
+    #[test]
+    fn detect_no_markers_returns_fallback_components() {
+        let dir = tempdir().unwrap();
+        let toml = detect_components_toml(dir.path());
+        // At least one [[component]] entry should always be present
+        assert!(
+            toml.contains("[[component]]"),
+            "should always emit at least one component"
+        );
+        // The fallback should include example backend and frontend entries
+        assert!(
+            toml.contains("name = \"backend\"") || toml.contains("name = \"frontend\""),
+            "fallback should include example component entries"
+        );
+    }
+
+    #[test]
+    fn detect_cargo_toml_generates_rust_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("Cargo.toml"), "[package]\nname = \"test\"\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"server\""));
+        assert!(toml.contains("setup = [\"cargo check\"]"));
+    }
+
+    #[test]
+    fn detect_package_json_with_pnpm_lock_generates_pnpm_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("package.json"), "{}").unwrap();
+        fs::write(dir.path().join("pnpm-lock.yaml"), "").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"frontend\""));
+        assert!(toml.contains("setup = [\"pnpm install\"]"));
+    }
+
+    #[test]
+    fn detect_package_json_without_pnpm_lock_generates_npm_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("package.json"), "{}").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"frontend\""));
+        assert!(toml.contains("setup = [\"npm install\"]"));
+    }
+
+    #[test]
+    fn detect_pyproject_toml_generates_python_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("pyproject.toml"), "[project]\nname = \"test\"\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"python\""));
+        assert!(toml.contains("pip install"));
+    }
+
+    #[test]
+    fn detect_requirements_txt_generates_python_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("requirements.txt"), "flask\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"python\""));
+        assert!(toml.contains("pip install"));
+    }
+
+    #[test]
+    fn detect_go_mod_generates_go_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("go.mod"), "module example.com/app\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"go\""));
+        assert!(toml.contains("setup = [\"go build ./...\"]"));
+    }
+
+    #[test]
+    fn detect_gemfile_generates_ruby_component() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("Gemfile"), "source \"https://rubygems.org\"\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"ruby\""));
+        assert!(toml.contains("setup = [\"bundle install\"]"));
+    }
+
+    #[test]
+    fn detect_multiple_markers_generates_multiple_components() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("Cargo.toml"), "[package]\nname = \"server\"\n").unwrap();
+        fs::write(dir.path().join("package.json"), "{}").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        assert!(toml.contains("name = \"server\""));
+        assert!(toml.contains("name = \"frontend\""));
+        // Both component entries should be present
+        let component_count = toml.matches("[[component]]").count();
+        assert_eq!(component_count, 2);
+    }
+
+    #[test]
+    fn detect_no_fallback_when_markers_found() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("Cargo.toml"), "[package]\nname = \"x\"\n").unwrap();
+
+        let toml = detect_components_toml(dir.path());
+        // The fallback "app" component should NOT appear when a real stack is detected
+        assert!(!toml.contains("name = \"app\""));
+    }
+
+    // --- generate_project_toml ---
+
+    #[test]
+    fn generate_project_toml_includes_both_components_and_agents() {
+        let dir = tempdir().unwrap();
+        fs::write(dir.path().join("Cargo.toml"), "[package]\nname = \"x\"\n").unwrap();
+
+        let toml = generate_project_toml(dir.path());
+        // Component section
+        assert!(toml.contains("[[component]]"));
+        assert!(toml.contains("name = \"server\""));
+        // Agent sections
+        assert!(toml.contains("[[agent]]"));
+        assert!(toml.contains("stage = \"coder\""));
+        assert!(toml.contains("stage = \"qa\""));
+        assert!(toml.contains("stage = \"mergemaster\""));
+    }
+
+    #[test]
+    fn scaffold_project_toml_contains_detected_components() {
+        let dir = tempdir().unwrap();
+        // Place a Cargo.toml in the project root before scaffolding
+        fs::write(dir.path().join("Cargo.toml"), "[package]\nname = \"myapp\"\n").unwrap();
+
+        scaffold_story_kit(dir.path()).unwrap();
+
+        let content =
+            fs::read_to_string(dir.path().join(".story_kit/project.toml")).unwrap();
+        assert!(
+            content.contains("[[component]]"),
+            "project.toml should contain a component entry"
+        );
+        assert!(
+            content.contains("name = \"server\""),
+            "Rust project should have a 'server' component"
+        );
+        assert!(
+            content.contains("cargo check"),
+            "Rust component should have cargo check setup"
+        );
+    }
+
+    #[test]
+    fn scaffold_project_toml_fallback_when_no_stack_detected() {
+        let dir = tempdir().unwrap();
+        scaffold_story_kit(dir.path()).unwrap();
+
+        let content =
+            fs::read_to_string(dir.path().join(".story_kit/project.toml")).unwrap();
+        assert!(
+            content.contains("[[component]]"),
+            "project.toml should always have at least one component"
+        );
+        // Fallback emits example components so the scaffold is immediately usable
+        assert!(
+            content.contains("name = \"backend\"") || content.contains("name = \"frontend\""),
+            "fallback should include example component entries"
+        );
+    }
+
+    #[test]
+    fn scaffold_does_not_overwrite_existing_project_toml_with_components() {
+        let dir = tempdir().unwrap();
+        let sk_dir = dir.path().join(".story_kit");
+        fs::create_dir_all(&sk_dir).unwrap();
+        let existing = "[[component]]\nname = \"custom\"\npath = \".\"\nsetup = [\"make build\"]\n";
+        fs::write(sk_dir.join("project.toml"), existing).unwrap();
+
+        scaffold_story_kit(dir.path()).unwrap();
+
+        let content = fs::read_to_string(sk_dir.join("project.toml")).unwrap();
+        assert_eq!(
+            content, existing,
+            "scaffold should not overwrite existing project.toml"
+        );
+    }
 }