feat(ReadFiles): simplify content output for single file reads (#33)

Improve ReadFiles executor to return simplified content when reading a
single file instead of YAML-wrapped structure.

Changes:
- Single file: Return file content directly (string)
- Multiple files: Keep existing YAML structure with files array
- All other outputs unchanged (files, total_files, etc.)

Benefits:
- More intuitive for common single-file use case
- Easier to consume in workflow templates
- Backward compatible for multiple file scenarios

Updated test snapshots to reflect new behavior.

Author: ibacalu

README.md

@@ -327,7 +327,10 @@ Read files with glob patterns, multiple output modes, and automatic outline extr
 - Gitignore integration and file filtering
 - Size limits and file count limits
 - Multi-file reading in single block
-- YAML-formatted output
+- Smart output format:
+  - Single file: Direct content (string)
+  - Multiple files: YAML-formatted structure
+  - No files: Empty string
 
 **See examples:** `tests/workflows/core/file-operations/readfiles-test.yaml`
 

src/workflows_mcp/engine/executors_file.py

@@ -302,11 +302,22 @@ class ReadFilesOutput(BlockOutput):
     @computed_field  # type: ignore[prop-decorator]
     @property
     def content(self) -> str:
-        """YAML-formatted output (backward compatible).
+        """Content output - simplified for single file, YAML for multiple files.
 
-        Returns structured YAML with literal block scalars for file content.
+        No files: Returns empty string.
+        Single file: Returns the file content directly (string).
+        Multiple files: Returns YAML-formatted output with file list.
         Single source of truth: files list.
         """
+        # No files: return empty string
+        if not self.files:
+            return ""
+
+        # Single file: return content directly
+        if len(self.files) == 1:
+            return self.files[0].content
+
+        # Multiple files: use YAML format
         return self._format_as_yaml()
 
     def _format_as_yaml(self) -> str:

tests/snapshots/editfile-interpolation-test.json

@@ -2,7 +2,7 @@
   "outputs": {
     "all_operations_succeeded": true,
     "delete_lines_count": 2,
-    "final_content": "files:\n- path: test.py\n  content: |\n    # Test completed successfully: true\n    # Lines added: 1\n    # Modified by /tmp/editfile-interpolation-test\n    # Interpolated header\n    def test():\n        value = \"OPERATIONS_INTERPOLATED\"\n        logger.info(\"Hello, World!\")\n    # Extra line 1\n    # Extra line 2\n  size_bytes: 235",
+    "final_content": "# Test completed successfully: true\n# Lines added: 1\n# Modified by test_multiple_operations_interpolation\n# Interpolated header\ndef test():\n    value = \"OPERATIONS_INTERPOLATED\"\n    logger.info(\"Hello, World!\")\n# Extra line 1\n# Extra line 2",
     "insert_lines_count": 1,
     "operations_field_interpolation_success": true,
     "replace_text_lines_modified": 1

tests/snapshots/editfile-operations-test.json

@@ -2,7 +2,7 @@
   "outputs": {
     "delete_lines_success": true,
     "dry_run_success": true,
-    "final_content": "files:\n- path: test.py\n  content: |\n    \"\"\"Test module for EditFile operations.\"\"\"\n    def hello():\n        logger.info(\"Hello, Python!\")\n        return 0\n\n    def goodbye():\n  size_bytes: 119",
+    "final_content": "\"\"\"Test module for EditFile operations.\"\"\"\ndef hello():\n    logger.info(\"Hello, Python!\")\n    return 0\n\ndef goodbye():",
     "insert_lines_success": true,
     "lines_added": 1,
     "lines_removed": 2,

tests/snapshots/file-operations-create-read.json

@@ -1,6 +1,5 @@
 {
   "outputs": {
-    "cleanup_done": true,
     "executable_file_created": true,
     "file_content": "# Testing file OPS\n\nGenerated: TIMESTAMP\nShell Output: data_from_shell\nUTF8 Content: \u4f60\u597d\u4e16\u754c\n\n## Features\n- Feature 1\n- Feature 2\n- Feature 3",
     "file_created": true,

tests/snapshots/filters-chaining.json

@@ -1,7 +1,6 @@
 {
   "outputs": {
     "all_tests_passed": true,
-    "cleanup_done": true,
     "test_complex_chain_output": "Complex chain: 'hello_world' (length: 11)\nSUCCESS: trim -> lower -> replace -> length chain worked",
     "test_number_chain_output": "Number chain: '42' (length: 2)\nSUCCESS: abs -> string -> length chain worked",
     "test_output_chain_output": "SUCCESS: outputs -> field access -> filter chain worked\nFile size: 12 bytes, created: true",

tests/snapshots/readfiles-test.json

@@ -13,14 +13,14 @@
         "size_bytes": 464
       }
     ],
-    "md_outline_content": "files:\n- path: README.md\n  content: |-\n    --- README.md (11 lines) ---\n      \u251c\u2500\u2500 Test Project [1]\n        \u251c\u2500\u2500 Overview [3]\n          \u251c\u2500\u2500 Features [6]\n        \u251c\u2500\u2500 Usage [10]\n  size_bytes: 134",
+    "md_outline_content": "--- README.md (11 lines) ---\n  \u251c\u2500\u2500 Test Project [1]\n    \u251c\u2500\u2500 Overview [3]\n      \u251c\u2500\u2500 Features [6]\n    \u251c\u2500\u2500 Usage [10]",
     "multi_full_content": "files:\n- path: README.md\n  content: |\n    # Test Project\n\n    ## Overview\n    This is a test project for ReadFiles.\n\n    ### Features\n    - Feature 1\n    - Feature 2\n\n    ## Usage\n    See examples below.\n  size_bytes: 134\n- path: example.py\n  content: |\n    \"\"\"Example Python module for testing.\"\"\"\n\n    def calculate_sum(a: int, b: int) -> int:\n        '''Add two numbers together.'''\n        return a + b\n\n    def calculate_product(a: int, b: int) -> int:\n        '''Multiply two numbers.'''\n        return a * b\n\n    class Calculator:\n        '''A simple calculator class.'''\n\n        def divide(self, a: float, b: float) -> float:\n            '''Divide a by b.'''\n            if b == 0:\n                raise ValueError(\"Cannot divide by zero\")\n            return a / b\n  size_bytes: 464\n",
     "multi_full_count": 2,
     "multi_full_size": 0,
-    "py_outline_content": "files:\n- path: example.py\n  content: |-\n    --- example.py (18 lines) ---\n      \u251c\u2500\u2500 def calculate_sum(a: int, b: int) -> int [3-5]\n      \u251c\u2500\u2500 def calculate_product(a: int, b: int) -> int [7-9]\n      \u251c\u2500\u2500 class Calculator [11-18]\n      \u2502   \u251c\u2500\u2500 def divide(self, a: float, b: float) -> float [14-18]\n  size_bytes: 464",
+    "py_outline_content": "--- example.py (18 lines) ---\n  \u251c\u2500\u2500 def calculate_sum(a: int, b: int) -> int [3-5]\n  \u251c\u2500\u2500 def calculate_product(a: int, b: int) -> int [7-9]\n  \u251c\u2500\u2500 class Calculator [11-18]\n  \u2502   \u251c\u2500\u2500 def divide(self, a: float, b: float) -> float [14-18]",
     "py_outline_count": 1,
-    "py_summary_content": "files:\n- path: example.py\n  content: |-\n    --- example.py (18 lines) ---\n      \u251c\u2500\u2500 def calculate_sum(a: int, b: int) -> int [3-5]\n      \u2502   \u2514\u2500\u2500 \"Add two numbers together....\"\n      \u251c\u2500\u2500 def calculate_product(a: int, b: int) -> int [7-9]\n      \u2502   \u2514\u2500\u2500 \"Multiply two numbers....\"\n      \u251c\u2500\u2500 class Calculator [11-18]\n      \u2502   \u2514\u2500\u2500 \"A simple calculator class....\"\n      \u2502   \u251c\u2500\u2500 def divide(self, a: float, b: float) -> float [14-18]\n      \u2502   \u2502   \u2514\u2500\u2500 \"Divide a by b....\"\n  size_bytes: 464",
-    "single_full_content": "files:\n- path: example.py\n  content: |\n    \"\"\"Example Python module for testing.\"\"\"\n\n    def calculate_sum(a: int, b: int) -> int:\n        '''Add two numbers together.'''\n        return a + b\n\n    def calculate_product(a: int, b: int) -> int:\n        '''Multiply two numbers.'''\n        return a * b\n\n    class Calculator:\n        '''A simple calculator class.'''\n\n        def divide(self, a: float, b: float) -> float:\n            '''Divide a by b.'''\n            if b == 0:\n                raise ValueError(\"Cannot divide by zero\")\n            return a / b\n  size_bytes: 464"
+    "py_summary_content": "--- example.py (18 lines) ---\n  \u251c\u2500\u2500 def calculate_sum(a: int, b: int) -> int [3-5]\n  \u2502   \u2514\u2500\u2500 \"Add two numbers together....\"\n  \u251c\u2500\u2500 def calculate_product(a: int, b: int) -> int [7-9]\n  \u2502   \u2514\u2500\u2500 \"Multiply two numbers....\"\n  \u251c\u2500\u2500 class Calculator [11-18]\n  \u2502   \u2514\u2500\u2500 \"A simple calculator class....\"\n  \u2502   \u251c\u2500\u2500 def divide(self, a: float, b: float) -> float [14-18]\n  \u2502   \u2502   \u2514\u2500\u2500 \"Divide a by b....\"",
+    "single_full_content": "\"\"\"Example Python module for testing.\"\"\"\n\ndef calculate_sum(a: int, b: int) -> int:\n    '''Add two numbers together.'''\n    return a + b\n\ndef calculate_product(a: int, b: int) -> int:\n    '''Multiply two numbers.'''\n    return a * b\n\nclass Calculator:\n    '''A simple calculator class.'''\n\n    def divide(self, a: float, b: float) -> float:\n        '''Divide a by b.'''\n        if b == 0:\n            raise ValueError(\"Cannot divide by zero\")\n        return a / b"
   },
   "status": "success"
 }

tests/workflows/core/file-operations/create-read.yaml

@@ -2,11 +2,6 @@ name: file-operations-create-read
 description: Test CreateFile with Jinja2 templates and variables
 tags: [test, core, files, create, read]
 inputs:
-  path:
-    type: str
-    description: "Temporary workspace"
-    default: "/tmp/test-create-read"
-
   features:
     description: Feature list
     type: list
@@ -24,7 +19,7 @@ blocks:
   - id: create_executable
     type: CreateFile
     inputs:
-      path: "{{inputs.path}}/script.sh"
+      path: "{{tmp}}/script.sh"
       create_parents: true
       mode: "755"
       content: |
@@ -34,14 +29,14 @@ blocks:
   - id: verify_executable
     type: Shell
     inputs:
-      working_dir: "{{inputs.path}}"
+      working_dir: "{{tmp}}"
       command: test -x "script.sh" && echo "yes"
     depends_on: [create_executable]
 
   - id: create_file
     type: CreateFile
     inputs:
-      path: "{{inputs.path}}/README.md"
+      path: "{{tmp}}/README.md"
       create_parents: true
       overwrite: true
       encoding: "utf-8"
@@ -62,42 +57,26 @@ blocks:
     type: ReadFiles
     inputs:
       patterns: ["README.md"]
-      base_path: "{{inputs.path}}"
+      base_path: "{{tmp}}"
     depends_on: [create_file]
 
   - id: read_nonexistent
     type: ReadFiles
     inputs:
       patterns: ["nonexistent.txt"]
-      base_path: "{{inputs.path}}"
+      base_path: "{{tmp}}"
     depends_on: [shell_data]
 
-  - id: cleanup
-    type: Shell
-    inputs:
-      command: |
-        # Safe cleanup with validation
-        DIR="{{inputs.path}}"
-        if [[ "$DIR" == /tmp/* ]] && [ -d "$DIR" ]; then
-          rm -rf "$DIR"
-        fi
-    depends_on:
-      - block: read_file
-        required: false
-
 outputs:
   file_created:
     value: "{{blocks.create_file.succeeded}}"
     type: bool
   file_content:
-    value: "{{get(blocks.read_file.outputs.files, 0, {}).content | default('Error: Failed to read file content')}}"
+    value: "{{blocks.read_file.content}}"
     type: str
   nonexistent_file_found:
     value: "{{blocks.read_nonexistent.succeeded}}"
     type: bool
   executable_file_created:
     value: "{{blocks.verify_executable.succeeded}}"
     type: bool
-  cleanup_done:
-    value: "{{blocks.cleanup.succeeded}}"
-    type: bool

tests/workflows/core/file-operations/editfile-interpolation-test.yaml

@@ -13,10 +13,6 @@ description: Test EditFile operation field interpolation support
 tags: [test, editfile, interpolation]
 
 inputs:
-  test_dir:
-    type: str
-    description: Test directory path
-    default: "/tmp/editfile-interpolation-test"
   # String inputs for operation field interpolation
   search_text:
     type: str
@@ -53,7 +49,7 @@ blocks:
   - id: create_test_file
     type: CreateFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       content: |
         def test():
             value = "PLACEHOLDER"
@@ -68,7 +64,7 @@ blocks:
   - id: test_replace_text_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: replace_text
           old_text: "{{inputs.search_text}}"
@@ -81,7 +77,7 @@ blocks:
   - id: test_insert_lines_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: insert_lines
           line_start: 1
@@ -93,7 +89,7 @@ blocks:
   - id: test_regex_replace_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: regex_replace
           pattern: "{{inputs.regex_pattern}}"
@@ -106,7 +102,7 @@ blocks:
   - id: test_delete_lines_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: delete_lines
           line_start: "{{inputs.delete_start}}"
@@ -118,7 +114,7 @@ blocks:
   - id: test_multiple_operations_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         # Operation 1: Use variable for old_text
         - type: replace_text
@@ -128,15 +124,15 @@ blocks:
         # Operation 2: Use variable for content
         - type: insert_lines
           line_start: 1
-          content: "# Modified by {{inputs.test_dir}}"
+          content: "# Modified by test_multiple_operations_interpolation"
       backup: false
     depends_on: [test_delete_lines_interpolation]
 
   # Test 6: Nested variable references (block output interpolation)
   - id: test_nested_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: insert_lines
           line_start: 1
@@ -150,7 +146,7 @@ blocks:
   - id: store_operations
     type: WriteJSONState
     inputs:
-      path: "{{inputs.test_dir}}/operations.json"
+      path: "{{tmp}}/operations.json"
       data:
         operations:
           - type: "replace_text"
@@ -163,15 +159,15 @@ blocks:
   - id: read_operations
     type: ReadJSONState
     inputs:
-      path: "{{inputs.test_dir}}/operations.json"
+      path: "{{tmp}}/operations.json"
       required: true
     depends_on: [store_operations]
 
   # Test 9: Interpolate entire operations field from state
   - id: test_operations_interpolation
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations: "{{blocks.read_operations.outputs.data.operations}}"
       backup: false
     depends_on: [read_operations]
@@ -181,7 +177,7 @@ blocks:
     type: ReadFiles
     inputs:
       patterns: ["test.py"]
-      base_path: "{{inputs.test_dir}}"
+      base_path: "{{tmp}}"
       mode: full
     depends_on: [test_operations_interpolation]
 

tests/workflows/core/file-operations/editfile-operations-test.yaml

@@ -12,18 +12,12 @@ name: editfile-operations-test
 description: Test EditFile executor with all operation types
 tags: [test, editfile, files]
 
-inputs:
-  test_dir:
-    type: str
-    description: Test directory path
-    default: "/tmp/editfile-test"
-
 blocks:
   # Setup: Create test file
   - id: create_test_file
     type: CreateFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       content: |
         def hello():
             print("Hello, World!")
@@ -38,7 +32,7 @@ blocks:
   - id: test_replace_text
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: replace_text
           old_text: "Hello, World!"
@@ -51,7 +45,7 @@ blocks:
   - id: test_insert_lines
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: insert_lines
           line_start: 1
@@ -64,7 +58,7 @@ blocks:
   - id: test_delete_lines
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: delete_lines
           line_start: 7
@@ -76,7 +70,7 @@ blocks:
   - id: test_regex_replace
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: regex_replace
           pattern: 'print\("([^"]+)"\)'
@@ -89,7 +83,7 @@ blocks:
   - id: test_dry_run
     type: EditFile
     inputs:
-      path: "{{inputs.test_dir}}/test.py"
+      path: "{{tmp}}/test.py"
       operations:
         - type: replace_text
           old_text: "logger.info"
@@ -103,7 +97,7 @@ blocks:
     type: ReadFiles
     inputs:
       patterns: ["test.py"]
-      base_path: "{{inputs.test_dir}}"
+      base_path: "{{tmp}}"
       mode: full
     depends_on: [test_dry_run]