Initial schemas and validation with extension workplan

tests/test_schema_contract.py

@@ -0,0 +1,164 @@
+from pathlib import Path
+
+from click.testing import CliRunner
+
+from markitect_tool.cli import main
+from markitect_tool.schema import (
+    InvalidSchemaFormatError,
+    SchemaNotFoundError,
+    load_schema_file,
+    validate_markdown_file,
+    validate_schema,
+)
+
+
+SCHEMA_TEXT = """---
+schema-id: "https://example.test/schemas/document/v1"
+version: "1.0.0"
+status: "stable"
+---
+
+# Document Schema
+
+## Schema Definition
+
+```json
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "title": "Document Schema",
+  "type": "object",
+  "required": ["frontmatter", "headings"],
+  "properties": {
+    "frontmatter": {
+      "type": "object",
+      "required": ["title"],
+      "properties": {
+        "title": {"type": "string"}
+      }
+    },
+    "headings": {
+      "type": "array",
+      "minItems": 1,
+      "items": {
+        "type": "object",
+        "required": ["level", "text"],
+        "properties": {
+          "level": {"type": "integer"},
+          "text": {"type": "string"}
+        }
+      }
+    }
+  }
+}
+```
+"""
+
+
+def test_load_schema_file_extracts_metadata_and_json_schema(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+
+    loaded = load_schema_file(schema_file)
+
+    assert loaded.metadata["schema-id"] == "https://example.test/schemas/document/v1"
+    assert loaded.metadata["status"] == "stable"
+    assert loaded.schema["title"] == "Document Schema"
+    assert loaded.schema["x-markitect-source"]["format"] == "markdown"
+    assert loaded.source_path == str(schema_file)
+
+
+def test_load_schema_file_requires_json_block(tmp_path: Path):
+    schema_file = tmp_path / "missing.md"
+    schema_file.write_text("# Missing\n\nNo schema.", encoding="utf-8")
+
+    try:
+        load_schema_file(schema_file)
+    except SchemaNotFoundError as exc:
+        assert "No JSON schema found" in str(exc)
+    else:
+        raise AssertionError("expected SchemaNotFoundError")
+
+
+def test_load_schema_file_rejects_invalid_json(tmp_path: Path):
+    schema_file = tmp_path / "invalid.md"
+    schema_file.write_text("```json\n{invalid json}\n```", encoding="utf-8")
+
+    try:
+        load_schema_file(schema_file)
+    except InvalidSchemaFormatError as exc:
+        assert "Invalid JSON schema block" in str(exc)
+    else:
+        raise AssertionError("expected InvalidSchemaFormatError")
+
+
+def test_validate_markdown_file_returns_valid_result(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+    markdown_file = tmp_path / "document.md"
+    markdown_file.write_text("---\ntitle: Example\n---\n\n# Example\n\nBody.", encoding="utf-8")
+
+    result = validate_markdown_file(markdown_file, schema_file)
+
+    assert result.valid is True
+    assert result.violations == []
+    assert result.document_path == str(markdown_file)
+    assert result.schema_path == str(schema_file)
+
+
+def test_validate_markdown_file_reports_violations(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+    markdown_file = tmp_path / "document.md"
+    markdown_file.write_text("# Missing Title\n\nBody.", encoding="utf-8")
+
+    result = validate_markdown_file(markdown_file, schema_file)
+
+    assert result.valid is False
+    assert result.violations
+    assert result.violations[0].path == "$.frontmatter"
+    assert "title" in result.violations[0].message
+
+
+def test_validate_schema_reports_invalid_schema():
+    result = validate_schema({"type": 7})
+
+    assert result.valid is False
+    assert result.violations
+
+
+def test_mkt_validate_exits_zero_for_valid_document(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+    markdown_file = tmp_path / "document.md"
+    markdown_file.write_text("---\ntitle: Example\n---\n\n# Example\n", encoding="utf-8")
+
+    result = CliRunner().invoke(
+        main, ["validate", str(markdown_file), "--schema", str(schema_file)]
+    )
+
+    assert result.exit_code == 0
+    assert "valid" in result.output
+
+
+def test_mkt_validate_exits_nonzero_for_invalid_document(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+    markdown_file = tmp_path / "document.md"
+    markdown_file.write_text("# Missing Title\n", encoding="utf-8")
+
+    result = CliRunner().invoke(
+        main, ["validate", str(markdown_file), "--schema", str(schema_file)]
+    )
+
+    assert result.exit_code == 1
+    assert "invalid" in result.output
+
+
+def test_mkt_schema_validate(tmp_path: Path):
+    schema_file = tmp_path / "document-schema.md"
+    schema_file.write_text(SCHEMA_TEXT, encoding="utf-8")
+
+    result = CliRunner().invoke(main, ["schema", "validate", str(schema_file)])
+
+    assert result.exit_code == 0
+    assert "valid" in result.output