feat(diff): implement unified diff formatting for edit_file tool results

2026-03-09 22:18:54 +00:00
parent 4c53bb0480
commit aad431785c
5 changed files with 519 additions and 4 deletions
@@ -0,0 +1,246 @@
+"""Tests for EvoScientist.stream.diff_format module."""
+
+from __future__ import annotations
+
+import difflib
+from unittest import mock
+
+from EvoScientist.stream.diff_format import (
+    _detect_unicode_support,
+    _escape_markup,
+    build_edit_diff,
+    format_diff_rich,
+)
+
+
+# ---------------------------------------------------------------------------
+# _escape_markup
+# ---------------------------------------------------------------------------
+
+class TestEscapeMarkup:
+    def test_escapes_brackets(self):
+        assert _escape_markup("[bold]text[/bold]") == r"\[bold\]text\[/bold\]"
+
+    def test_plain_text_unchanged(self):
+        assert _escape_markup("hello world") == "hello world"
+
+    def test_empty_string(self):
+        assert _escape_markup("") == ""
+
+    def test_nested_brackets(self):
+        assert _escape_markup("a[b[c]]d") == r"a\[b\[c\]\]d"
+
+
+# ---------------------------------------------------------------------------
+# _detect_unicode_support
+# ---------------------------------------------------------------------------
+
+class TestDetectUnicodeSupport:
+    def test_utf8_encoding(self):
+        with mock.patch("sys.stdout") as mock_stdout:
+            mock_stdout.encoding = "utf-8"
+            assert _detect_unicode_support() is True
+
+    def test_ascii_encoding_with_utf_lang(self):
+        with mock.patch("sys.stdout") as mock_stdout:
+            mock_stdout.encoding = "ascii"
+            with mock.patch.dict("os.environ", {"LANG": "en_US.UTF-8", "LC_ALL": ""}):
+                assert _detect_unicode_support() is True
+
+    def test_ascii_encoding_no_utf_lang(self):
+        with mock.patch("sys.stdout") as mock_stdout:
+            mock_stdout.encoding = "ascii"
+            with mock.patch.dict(
+                "os.environ", {"LANG": "C", "LC_ALL": ""}, clear=False
+            ):
+                assert _detect_unicode_support() is False
+
+
+# ---------------------------------------------------------------------------
+# format_diff_rich
+# ---------------------------------------------------------------------------
+
+class TestFormatDiffRich:
+    def test_empty_diff_returns_dim_message(self):
+        result = format_diff_rich("")
+        assert "No changes detected" in result
+        assert "[dim]" in result
+
+    def test_single_line_change(self):
+        old = ["hello"]
+        new = ["world"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff)
+        # Should contain addition and deletion markers
+        assert "[green]+1[/green]" in result
+        assert "[red]-1[/red]" in result
+        # Deletion line (red background)
+        assert "2d1515" in result  # red background color
+        # Addition line (green background)
+        assert "152d15" in result  # green background color
+
+    def test_stats_header(self):
+        old = ["a", "b", "c"]
+        new = ["a", "x", "c", "d"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff)
+        # 1 deletion (b), 2 additions (x, d)
+        assert "[green]+2[/green]" in result
+        assert "[red]-1[/red]" in result
+
+    def test_max_lines_truncation(self):
+        old = [f"line{i}" for i in range(50)]
+        new = [f"LINE{i}" for i in range(50)]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=0))
+        result = format_diff_rich(diff, max_lines=10)
+        assert "more lines" in result
+
+    def test_context_lines_dimmed(self):
+        old = ["a", "b", "c"]
+        new = ["a", "B", "c"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff)
+        # Context lines should use dim styling
+        assert "[dim]" in result
+
+    def test_title_header(self):
+        old = ["hello"]
+        new = ["world"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff, title="/path/to/file.py")
+        # Title should appear with bold cyan and box-drawing chars
+        assert "file.py" in result
+        assert "[bold cyan]" in result
+
+    def test_title_none_omits_header(self):
+        old = ["hello"]
+        new = ["world"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff, title=None)
+        assert "[bold cyan]" not in result
+
+    def test_stats_footer(self):
+        old = ["a"]
+        new = ["b"]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=3))
+        result = format_diff_rich(diff)
+        # Stats should appear both at top and bottom
+        lines = result.splitlines()
+        # First non-empty line is stats header, last non-empty line is stats footer
+        non_empty = [ln for ln in lines if ln.strip()]
+        assert non_empty[0] == non_empty[-1]  # header == footer
+
+    def test_max_lines_none_unlimited(self):
+        old = [f"line{i}" for i in range(200)]
+        new = [f"LINE{i}" for i in range(200)]
+        diff = "\n".join(difflib.unified_diff(old, new, lineterm="", n=0))
+        result = format_diff_rich(diff, max_lines=None)
+        # Should NOT have truncation marker
+        assert "more lines" not in result
+
+
+# ---------------------------------------------------------------------------
+# build_edit_diff
+# ---------------------------------------------------------------------------
+
+class TestBuildEditDiff:
+    def test_returns_none_when_equal(self):
+        assert build_edit_diff("/foo.py", "same", "same") is None
+
+    def test_returns_none_when_both_empty(self):
+        assert build_edit_diff("/foo.py", "", "") is None
+
+    def test_returns_formatted_markup_for_valid_diff(self):
+        result = build_edit_diff(
+            "/foo.py",
+            "old line",
+            "new line",
+        )
+        assert result is not None
+        assert "[green]" in result
+        assert "[red]" in result
+
+    def test_multiline_diff(self):
+        old = "line1\nline2\nline3"
+        new = "line1\nmodified\nline3\nline4"
+        result = build_edit_diff("/test.py", old, new)
+        assert result is not None
+        assert "+2" in result  # 2 additions
+        assert "-1" in result  # 1 deletion
+
+    def test_no_truncation_by_default(self):
+        old = "\n".join(f"old{i}" for i in range(100))
+        new = "\n".join(f"new{i}" for i in range(100))
+        result = build_edit_diff("/big.py", old, new)
+        assert result is not None
+        # Default max_lines=None means no truncation
+        assert "more lines" not in result
+
+    def test_explicit_max_lines_truncates(self):
+        old = "\n".join(f"old{i}" for i in range(100))
+        new = "\n".join(f"new{i}" for i in range(100))
+        result = build_edit_diff("/big.py", old, new, max_lines=5)
+        assert result is not None
+        assert "more lines" in result
+
+    def test_file_path_shown_as_title(self):
+        result = build_edit_diff("/my/file.py", "a", "b")
+        assert result is not None
+        # File path should appear as the title header
+        assert "file.py" in result
+        assert "[bold cyan]" in result
+
+
+# ---------------------------------------------------------------------------
+# Integration with format_tool_result_compact
+# ---------------------------------------------------------------------------
+
+class TestFormatToolResultCompactEditFile:
+    def test_edit_file_with_tool_args_shows_diff(self):
+        from EvoScientist.stream.display import format_tool_result_compact
+
+        result = format_tool_result_compact(
+            "edit_file",
+            "[OK] Successfully replaced 1 instance(s)",
+            tool_args={
+                "path": "/foo.py",
+                "old_string": "hello",
+                "new_string": "world",
+            },
+        )
+        # Should return markup elements with diff content
+        assert len(result) >= 1
+        plain = result[0].plain if hasattr(result[0], "plain") else str(result[0])
+        assert "+1" in plain or "world" in plain or "hello" in plain
+
+    def test_edit_file_without_tool_args_falls_through(self):
+        from EvoScientist.stream.display import format_tool_result_compact
+
+        result = format_tool_result_compact(
+            "edit_file",
+            "[OK] Successfully replaced 1 instance(s)",
+        )
+        # Without tool_args, falls through to normal rendering
+        assert len(result) >= 1
+
+    def test_edit_file_error_shows_error_not_diff(self):
+        from EvoScientist.stream.display import format_tool_result_compact
+
+        result = format_tool_result_compact(
+            "edit_file",
+            "[ERROR] File not found",
+            tool_args={
+                "path": "/foo.py",
+                "old_string": "hello",
+                "new_string": "world",
+            },
+        )
+        # Error content should show error, not diff
+        assert len(result) >= 1
+
+    def test_backward_compatible_no_tool_args(self):
+        from EvoScientist.stream.display import format_tool_result_compact
+
+        # Existing calls without tool_args should still work
+        result = format_tool_result_compact("read_file", "[OK] 42 lines")
+        assert len(result) >= 1