Also check luatex version using the general executable checker.

anntzer · anntzer · commit 64f2b284acde · 2018-05-08T14:32:30.000-07:00
diff --git a/lib/matplotlib/__init__.py b/lib/matplotlib/__init__.py
@@ -423,11 +423,20 @@ def wrapper(*args, **kwargs):
 
 
 _ExecInfo = namedtuple("_ExecInfo", "executable version")
+# Moved out to allow unit-testing.
+_version_regexes = {
+    "dvipng": "(?m)^dvipng .* (.+)",
+    "gs": "(.*)",
+    "inkscape": "^Inkscape ([^ ]*)",
+    "luatex": r"^This is LuaTeX, Version (?:beta-)?(\d+\.\d+\.\d+)",
+    "pdftops": "^pdftops version (.*)",
+}
 
 
 @functools.lru_cache()
 def get_executable_info(name):
-    """Get the version of some executables that Matplotlib depends on.
+    """
+    Get the version of some executables that Matplotlib depends on.
 
     .. warning:
        The list of executables that this function supports is set according to
@@ -437,8 +446,8 @@ def get_executable_info(name):
     ----------
     name : str
         The executable to query.  The following values are currently supported:
-        "dvipng", "gs", "inkscape", "pdftops", "tex".  This list is subject to
-        change without notice.
+        "dvipng", "gs", "inkscape", "luatex", "pdftops", "tex".  This list is
+        subject to change without notice.
 
     Returns
     -------
@@ -473,19 +482,23 @@ def impl(args, regex, min_ver=None):
             return None
 
     if name == "dvipng":
-        info = impl(["dvipng", "-version"], "(?m)^dvipng .* (.+)", "1.6")
+        info = impl(["dvipng", "-version"], _version_regexes["dvipng"], "1.6")
     elif name == "gs":
         execs = (["gswin32c", "gswin64c", "mgs", "gs"]  # "mgs" for miktex.
                  if sys.platform == "win32" else
                  ["gs"])
-        info = next((info for info in (impl([e, "--version"], "(.*)", "9")
-                                       for e in execs)
-                     if info),
-                    None)
+        info = next(
+            (info for info in (
+                impl([e, "--version"], _version_regexes["gs"], "9")
+                for e in execs)
+             if info),
+            None)
     elif name == "inkscape":
-        info = impl(["inkscape", "-V"], "^Inkscape ([^ ]*)")
+        info = impl(["inkscape", "-V"], _version_regexes["inkscape"])
+    elif name == "luatex":
+        info = impl(["luatex", "--version"], _version_regexes["luatex"])
     elif name == "pdftops":
-        info = impl(["pdftops", "-v"], "^pdftops version (.*)")
+        info = impl(["pdftops", "-v"], _version_regexes["pdftops"])
         if info and not ("3.0" <= info.version
                          # poppler version numbers.
                          or "0.9" <= info.version <= "1.0"):
@@ -502,7 +515,8 @@ def impl(args, regex, min_ver=None):
 
 
 def get_all_executable_infos():
-    """Query all executables that Matplotlib may need.
+    """
+    Query all executables that Matplotlib may need.
 
     .. warning:
        The list of executables that this function queries is set according to
@@ -515,7 +529,8 @@ def get_all_executable_infos():
     to change without notice.
     """
     return {name: get_executable_info(name)
-            for name in ["dvipng", "gs", "inkscape", "pdftops", "tex"]}
+            for name in ["dvipng", "gs", "inkscape", "luatex", "pdftops",
+                         "tex"]}
 
 
 @cbook.deprecated("3.0")
diff --git a/lib/matplotlib/backends/backend_pgf.py b/lib/matplotlib/backends/backend_pgf.py
@@ -30,11 +30,6 @@
 ###############################################################################
 
 
-_luatex_version_re = re.compile(
-    r'This is LuaTeX, Version (?:beta-)?([0-9]+)\.([0-9]+)\.([0-9]+)'
-)
-
-
 @cbook.deprecated("3.0")
 def get_texcommand():
     """Get chosen TeX system from rc."""
@@ -43,18 +38,6 @@ def get_texcommand():
     return texsystem if texsystem in texsystem_options else "xelatex"
 
 
-def _get_lualatex_version():
-    """Get version of luatex"""
-    output = subprocess.check_output(['lualatex', '--version'])
-    return _parse_lualatex_version(output.decode())
-
-
-def _parse_lualatex_version(output):
-    '''parse the lualatex version from the output of `lualatex --version`'''
-    match = _luatex_version_re.match(output)
-    return tuple(map(int, match.groups()))
-
-
 def get_fontspec():
     """Build fontspec preamble from rc."""
     latex_fontspec = []
@@ -1166,8 +1149,8 @@ def _build_newpage_command(self, width, height):
         so we need to check the lualatex version and use `\pagewidth` if
         the version is 0.85 or newer
         '''
-        texcommand = get_texcommand()
-        if texcommand == 'lualatex' and _get_lualatex_version() >= (0, 85, 0):
+        if (get_texcommand() == 'lualatex'
+                and mpl.get_executable_info('luatex').version >= '0.85'):
             cmd = r'\page'
         else:
             cmd = r'\pdfpage'
diff --git a/lib/matplotlib/tests/test_backend_pgf.py b/lib/matplotlib/tests/test_backend_pgf.py
@@ -1,5 +1,6 @@
 import os
 from pathlib import Path
+import re
 import shutil
 import subprocess
 from tempfile import TemporaryDirectory
@@ -272,11 +273,7 @@ def test_pdf_pages_lualatex():
         assert pdf.get_pagecount() == 2
 
 
-@needs_lualatex
 def test_luatex_version():
-    from matplotlib.backends.backend_pgf import _parse_lualatex_version
-    from matplotlib.backends.backend_pgf import _get_lualatex_version
-
     v1 = '''This is LuaTeX, Version 1.0.4 (TeX Live 2017)
 
 Execute  'luatex --credits'  for credits and version details.
@@ -301,9 +298,5 @@ def test_luatex_version():
 Copyright 2013 Taco Hoekwater, the LuaTeX Team.
 '''
 
-    assert _parse_lualatex_version(v1) == (1, 0, 4)
-    assert _parse_lualatex_version(v2) == (0, 76, 0)
-
-    # just test if it is successful
-    version = _get_lualatex_version()
-    assert len(version) == 3
+    assert re.search(mpl._version_regexes["luatex"], v1).group(1) == "1.0.4"
+    assert re.search(mpl._version_regexes["luatex"], v2).group(1) == "0.76.0"
