matplotlib · ksunden · Sep 4, 2023 · Sep 4, 2023
diff --git a/lib/matplotlib/backends/backend_pgf.py b/lib/matplotlib/backends/backend_pgf.py
@@ -241,24 +241,14 @@ def __init__(self):
        self._finalize_tmpdir = weakref.finalize(self, self._tmpdir.cleanup)

        # test the LaTeX setup to ensure a clean startup of the subprocess
-        try:
-            self._setup_latex_process(expect_reply=False)
-        except FileNotFoundError as err:
-            raise RuntimeError(
-                f"{self.latex.args[0]!r} not found.  Install it or change "
-                f"rcParams['pgf.texsystem'] to an available TeX "
-                f"implementation.") from err
-        except OSError as err:
-            raise RuntimeError(
-                f"Error starting process {self.latex.args[0]!r}") from err
+        self._setup_latex_process(expect_reply=False)
        stdout, stderr = self.latex.communicate("\n\\makeatletter\\@@end\n")
        if self.latex.returncode != 0:
            raise LatexError(
                f"LaTeX errored (probably missing font or error in preamble) "
                f"while processing the following input:\n"
                f"{self._build_latex_header()}",
                stdout)
-
        self.latex = None  # Will be set up on first use.
        # Per-instance cache.
        self._get_box_metrics = functools.lru_cache(self._get_box_metrics)
@@ -268,10 +258,19 @@ def _setup_latex_process(self, *, expect_reply=True):
        # Windows, we must ensure that the subprocess has quit before being
        # able to delete the tmpdir in which it runs; in order to do so, we
        # must first `kill()` it, and then `communicate()` with it.
-        self.latex = subprocess.Popen(
-            [mpl.rcParams["pgf.texsystem"], "-halt-on-error"],
-            stdin=subprocess.PIPE, stdout=subprocess.PIPE,
-            encoding="utf-8", cwd=self.tmpdir)
+        try:
+            self.latex = subprocess.Popen(
+                [mpl.rcParams["pgf.texsystem"], "-halt-on-error"],
+                stdin=subprocess.PIPE, stdout=subprocess.PIPE,
+                encoding="utf-8", cwd=self.tmpdir)
+        except FileNotFoundError as err:
+            raise RuntimeError(
+                f"{mpl.rcParams['pgf.texsystem']!r} not found; install it or change "
+                f"rcParams['pgf.texsystem'] to an available TeX implementation"
+            ) from err
+        except OSError as err:
+            raise RuntimeError(
+                f"Error starting {mpl.rcParams['pgf.texsystem']!r}") from err

        def finalize_latex(latex):
            latex.kill()