Merge pull request matplotlib#30431 from anntzer/tp

Use pathlib in texmanager.

Author: QuLogic

lib/matplotlib/texmanager.py

@@ -23,7 +23,6 @@
 import functools
 import hashlib
 import logging
-import os
 from pathlib import Path
 import subprocess
 from tempfile import TemporaryDirectory
@@ -63,7 +62,7 @@ class TexManager:
     Repeated calls to this constructor always return the same instance.
     """
 
-    _texcache = os.path.join(mpl.get_cachedir(), 'tex.cache')
+    _cache_dir = Path(mpl.get_cachedir(), 'tex.cache')
     _grey_arrayd = {}
 
     _font_families = ('serif', 'sans-serif', 'cursive', 'monospace')
@@ -109,7 +108,7 @@ class TexManager:
 
     @functools.lru_cache  # Always return the same instance.
     def __new__(cls):
-        Path(cls._texcache).mkdir(parents=True, exist_ok=True)
+        cls._cache_dir.mkdir(parents=True, exist_ok=True)
         return object.__new__(cls)
 
     @classmethod
@@ -167,23 +166,30 @@ def _get_font_preamble_and_command(cls):
         return preamble, fontcmd
 
     @classmethod
-    def get_basefile(cls, tex, fontsize, dpi=None):
+    def _get_base_path(cls, tex, fontsize, dpi=None):
         """
-        Return a filename based on a hash of the string, fontsize, and dpi.
+        Return a file path based on a hash of the string, fontsize, and dpi.
         """
         src = cls._get_tex_source(tex, fontsize) + str(dpi)
         filehash = hashlib.sha256(
             src.encode('utf-8'),
             usedforsecurity=False
         ).hexdigest()
-        filepath = Path(cls._texcache)
+        filepath = cls._cache_dir
 
         num_letters, num_levels = 2, 2
         for i in range(0, num_letters*num_levels, num_letters):
-            filepath = filepath / Path(filehash[i:i+2])
+            filepath = filepath / filehash[i:i+2]
 
         filepath.mkdir(parents=True, exist_ok=True)
-        return os.path.join(filepath, filehash)
+        return filepath / filehash
+
+    @classmethod
+    def get_basefile(cls, tex, fontsize, dpi=None):  # Kept for backcompat.
+        """
+        Return a filename based on a hash of the string, fontsize, and dpi.
+        """
+        return str(cls._get_base_path(tex, fontsize, dpi))
 
     @classmethod
     def get_font_preamble(cls):
@@ -241,17 +247,16 @@ def make_tex(cls, tex, fontsize):
 
         Return the file name.
         """
-        texfile = cls.get_basefile(tex, fontsize) + ".tex"
-        Path(texfile).write_text(cls._get_tex_source(tex, fontsize),
-                                 encoding='utf-8')
-        return texfile
+        texpath = cls._get_base_path(tex, fontsize).with_suffix(".tex")
+        texpath.write_text(cls._get_tex_source(tex, fontsize), encoding='utf-8')
+        return str(texpath)
 
     @classmethod
     def _run_checked_subprocess(cls, command, tex, *, cwd=None):
         _log.debug(cbook._pformat_subprocess(command))
         try:
             report = subprocess.check_output(
-                command, cwd=cwd if cwd is not None else cls._texcache,
+                command, cwd=cwd if cwd is not None else cls._cache_dir,
                 stderr=subprocess.STDOUT)
         except FileNotFoundError as exc:
             raise RuntimeError(
@@ -279,8 +284,8 @@ def make_dvi(cls, tex, fontsize):
 
         Return the file name.
         """
-        dvifile = Path(cls.get_basefile(tex, fontsize)).with_suffix(".dvi")
-        if not dvifile.exists():
+        dvipath = cls._get_base_path(tex, fontsize).with_suffix(".dvi")
+        if not dvipath.exists():
             # Generate the tex and dvi in a temporary directory to avoid race
             # conditions e.g. if multiple processes try to process the same tex
             # string at the same time.  Having tmpdir be a subdirectory of the
@@ -290,17 +295,17 @@ def make_dvi(cls, tex, fontsize):
             # the absolute path may contain characters (e.g. ~) that TeX does
             # not support; n.b. relative paths cannot traverse parents, or it
             # will be blocked when `openin_any = p` in texmf.cnf).
-            with TemporaryDirectory(dir=dvifile.parent) as tmpdir:
+            with TemporaryDirectory(dir=dvipath.parent) as tmpdir:
                 Path(tmpdir, "file.tex").write_text(
                     cls._get_tex_source(tex, fontsize), encoding='utf-8')
                 cls._run_checked_subprocess(
                     ["latex", "-interaction=nonstopmode", "--halt-on-error",
                      "file.tex"], tex, cwd=tmpdir)
-                Path(tmpdir, "file.dvi").replace(dvifile)
+                Path(tmpdir, "file.dvi").replace(dvipath)
                 # Also move the tex source to the main cache directory, but
                 # only for backcompat.
-                Path(tmpdir, "file.tex").replace(dvifile.with_suffix(".tex"))
-        return str(dvifile)
+                Path(tmpdir, "file.tex").replace(dvipath.with_suffix(".tex"))
+        return str(dvipath)
 
     @classmethod
     def make_png(cls, tex, fontsize, dpi):
@@ -309,13 +314,12 @@ def make_png(cls, tex, fontsize, dpi):
 
         Return the file name.
         """
-        pngfile = Path(cls.get_basefile(tex, fontsize)).with_suffix(".png")
-        # see get_rgba for a discussion of the background
-        if not pngfile.exists():
-            dvifile = cls.make_dvi(tex, fontsize)
-            with TemporaryDirectory(dir=pngfile.parent) as tmpdir:
+        pngpath = cls._get_base_path(tex, fontsize, dpi).with_suffix(".png")
+        if not pngpath.exists():
+            dvipath = cls.make_dvi(tex, fontsize)
+            with TemporaryDirectory(dir=pngpath.parent) as tmpdir:
                 cmd = ["dvipng", "-bg", "Transparent", "-D", str(dpi),
-                       "-T", "tight", "-o", "file.png", dvifile]
+                       "-T", "tight", "-o", "file.png", dvipath]
                 # When testing, disable FreeType rendering for reproducibility;
                 # but dvipng 1.16 has a bug (fixed in f3ff241) that breaks
                 # --freetype0 mode, so for it we keep FreeType enabled; the
@@ -324,8 +328,8 @@ def make_png(cls, tex, fontsize, dpi):
                         mpl._get_executable_info("dvipng").raw_version != "1.16"):
                     cmd.insert(1, "--freetype0")
                 cls._run_checked_subprocess(cmd, tex, cwd=tmpdir)
-                Path(tmpdir, "file.png").replace(pngfile)
-        return str(pngfile)
+                Path(tmpdir, "file.png").replace(pngpath)
+        return str(pngpath)
 
     @classmethod
     def get_grey(cls, tex, fontsize=None, dpi=None):
@@ -336,7 +340,7 @@ def get_grey(cls, tex, fontsize=None, dpi=None):
         alpha = cls._grey_arrayd.get(key)
         if alpha is None:
             pngfile = cls.make_png(tex, fontsize, dpi)
-            rgba = mpl.image.imread(os.path.join(cls._texcache, pngfile))
+            rgba = mpl.image.imread(pngfile)
             cls._grey_arrayd[key] = alpha = rgba[:, :, -1]
         return alpha
 
@@ -362,9 +366,9 @@ def get_text_width_height_descent(cls, tex, fontsize, renderer=None):
         """Return width, height and descent of the text."""
         if tex.strip() == '':
             return 0, 0, 0
-        dvifile = cls.make_dvi(tex, fontsize)
+        dvipath = cls.make_dvi(tex, fontsize)
         dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
-        with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:
+        with dviread.Dvi(dvipath, 72 * dpi_fraction) as dvi:
             page, = dvi
         # A total height (including the descent) needs to be returned.
         return page.width, page.height + page.descent, page.descent