From 76e044477010dcc0e31d4a736b7130e044a01a7e Mon Sep 17 00:00:00 2001
From: Leonardus Chen <leonardus.chen@gmail.com>
Date: Mon, 25 Nov 2024 19:25:50 +0700
Subject: [PATCH] pytest.fail: fix ANSI escape codes for colored output
 (#12959)

- When `ReprEntry.style == "value"` (happens when calling `pytest.fail(..., pytrace=False)`, the message should not be printed to terminal using `TerminalWriter._write_source` because then it'll try to highlight the message as source code
- The message should be printed to terminal directly using `TerminalWriter.line` or `TerminalWriter.write`, I went with the later for testing purposes https://github.com/pytest-dev/pytest/pull/12959#discussion_r1842574618

Closes #12849
---
 AUTHORS                      |  1 +
 changelog/12849.bugfix.rst   |  1 +
 src/_pytest/_code/code.py    | 16 +++++++++++-----
 testing/code/test_excinfo.py | 17 +++++++++++++++++
 testing/conftest.py          |  4 ++--
 5 files changed, 32 insertions(+), 7 deletions(-)
 create mode 100644 changelog/12849.bugfix.rst

diff --git a/AUTHORS b/AUTHORS
index c38f74d9980..303d04133cb 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -247,6 +247,7 @@ Kristoffer Nordström
 Kyle Altendorf
 Lawrence Mitchell
 Lee Kamentsky
+Leonardus Chen
 Lev Maximov
 Levon Saldamli
 Lewis Cowles
diff --git a/changelog/12849.bugfix.rst b/changelog/12849.bugfix.rst
new file mode 100644
index 00000000000..fb72263aadd
--- /dev/null
+++ b/changelog/12849.bugfix.rst
@@ -0,0 +1 @@
+ANSI escape codes for colored output now handled correctly in :func:`pytest.fail` with `pytrace=False`.
diff --git a/src/_pytest/_code/code.py b/src/_pytest/_code/code.py
index 8fac39ea298..fec627b3a36 100644
--- a/src/_pytest/_code/code.py
+++ b/src/_pytest/_code/code.py
@@ -1221,6 +1221,15 @@ def _write_entry_lines(self, tw: TerminalWriter) -> None:
         if not self.lines:
             return
 
+        if self.style == "value":
+            # Using tw.write instead of tw.line for testing purposes due to TWMock implementation;
+            # lines written with TWMock.line and TWMock._write_source cannot be distinguished
+            # from each other, whereas lines written with TWMock.write are marked with TWMock.WRITE
+            for line in self.lines:
+                tw.write(line)
+                tw.write("\n")
+            return
+
         # separate indents and source lines that are not failures: we want to
         # highlight the code but not the indentation, which may contain markers
         # such as ">   assert 0"
@@ -1236,11 +1245,8 @@ def _write_entry_lines(self, tw: TerminalWriter) -> None:
                 failure_lines.extend(self.lines[index:])
                 break
             else:
-                if self.style == "value":
-                    source_lines.append(line)
-                else:
-                    indents.append(line[:indent_size])
-                    source_lines.append(line[indent_size:])
+                indents.append(line[:indent_size])
+                source_lines.append(line[indent_size:])
 
         tw._write_source(source_lines, indents)
 
diff --git a/testing/code/test_excinfo.py b/testing/code/test_excinfo.py
index fc60ae9ac99..97c207e9795 100644
--- a/testing/code/test_excinfo.py
+++ b/testing/code/test_excinfo.py
@@ -1194,6 +1194,23 @@ def f():
         line = tw_mock.lines[-1]
         assert line == ":3: ValueError"
 
+    def test_toterminal_value(self, importasmod, tw_mock):
+        mod = importasmod(
+            """
+            def g(x):
+                raise ValueError(x)
+            def f():
+                g('some_value')
+        """
+        )
+        excinfo = pytest.raises(ValueError, mod.f)
+        excinfo.traceback = excinfo.traceback.filter(excinfo)
+        repr = excinfo.getrepr(style="value")
+        repr.toterminal(tw_mock)
+
+        assert tw_mock.get_write_msg(0) == "some_value"
+        assert tw_mock.get_write_msg(1) == "\n"
+
     @pytest.mark.parametrize(
         "reproptions",
         [
diff --git a/testing/conftest.py b/testing/conftest.py
index 046bb77a109..69af03324d6 100644
--- a/testing/conftest.py
+++ b/testing/conftest.py
@@ -119,8 +119,8 @@ def markup(self, text, **kw):
             return text
 
         def get_write_msg(self, idx):
-            flag, msg = self.lines[idx]
-            assert flag == TWMock.WRITE
+            assert self.lines[idx][0] == TWMock.WRITE
+            msg = self.lines[idx][1]
             return msg
 
         fullwidth = 80