import re

from tempfile import TemporaryFile

import numpy as np

from packaging.version import parse as parse_version

import pytest

import matplotlib as mpl

from matplotlib import dviread

from matplotlib.testing import _has_tex_package

from matplotlib.testing.decorators import check_figures_equal, image_comparison

from matplotlib.testing._markers import needs_usetex

import matplotlib.pyplot as plt

pytestmark = needs_usetex

@image_comparison(

baseline_images=['test_usetex'],

extensions=['pdf', 'png'],

style="mpl20")

def test_usetex():

mpl.rcParams['text.usetex'] = True

fig, ax = plt.subplots()

kwargs = {"verticalalignment": "baseline", "size": 24,

"bbox": dict(pad=0, edgecolor="k", facecolor="none")}

ax.text(0.2, 0.7,

# the \LaTeX macro exercises character sizing and placement,

# \left[ ... \right\} draw some variable-height characters,

# \sqrt and \frac draw horizontal rules, \mathrm changes the font

r'\LaTeX\ $\left[\int\limits_e^{2e}'

r'\sqrt\frac{\log^3 x}{x}\,\mathrm{d}x \right\}$',

**kwargs)

ax.text(0.2, 0.3, "lg", **kwargs)

ax.text(0.4, 0.3, r"$\frac{1}{2}\pi$", **kwargs)

ax.text(0.6, 0.3, "$p^{3^A}$", **kwargs)

ax.text(0.8, 0.3, "$p_{3_2}$", **kwargs)

for x in {t.get_position()[0] for t in ax.texts}:

ax.axvline(x)

for y in {t.get_position()[1] for t in ax.texts}:

ax.axhline(y)

ax.set_axis_off()

@check_figures_equal(extensions=['png', 'pdf', 'svg'])

def test_empty(fig_test, fig_ref):

mpl.rcParams['text.usetex'] = True

fig_test.text(.5, .5, "% a comment")

@check_figures_equal(extensions=['png', 'pdf', 'svg'])

def test_unicode_minus(fig_test, fig_ref):

mpl.rcParams['text.usetex'] = True

fig_test.text(.5, .5, "$-$")

fig_ref.text(.5, .5, "\N{MINUS SIGN}")

def test_mathdefault():

plt.rcParams["axes.formatter.use_mathtext"] = True

fig = plt.figure()

fig.add_subplot().set_xlim(-1, 1)

# Check that \mathdefault commands generated by tickers don't cause

# problems when later switching usetex on.

mpl.rcParams['text.usetex'] = True

fig.canvas.draw()

@image_comparison(['eqnarray.png'], style='mpl20')

def test_multiline_eqnarray():

text = (

r'\begin{eqnarray*}'

r'foo\\'

r'bar\\'

r'baz\\'

r'\end{eqnarray*}'

)

fig = plt.figure(figsize=(1, 1))

fig.text(0.5, 0.5, text, usetex=True,

horizontalalignment='center', verticalalignment='center')

@pytest.mark.parametrize("fontsize", [8, 10, 12])

def test_minus_no_descent(fontsize):

# Test special-casing of minus descent in DviFont._height_depth_of, by

# checking that overdrawing a 1 and a -1 results in an overall height

# equivalent to drawing either of them separately.

mpl.style.use("mpl20")

mpl.rcParams['font.size'] = fontsize

heights = {}

fig = plt.figure()

for vals in [(1,), (-1,), (-1, 1)]:

fig.clear()

for x in vals:

fig.text(.5, .5, f"${x}$", usetex=True)

fig.canvas.draw()

# The following counts the number of non-fully-blank pixel rows.

heights[vals] = ((np.array(fig.canvas.buffer_rgba())[..., 0] != 255)

.any(axis=1).sum())

assert len({*heights.values()}) == 1

@pytest.mark.parametrize('pkg', ['xcolor', 'chemformula'])

def test_usetex_packages(pkg):

if not _has_tex_package(pkg):

pytest.skip(f'{pkg} is not available')

mpl.rcParams['text.usetex'] = True

fig = plt.figure()

text = fig.text(0.5, 0.5, "Some text 0123456789")

fig.canvas.draw()

mpl.rcParams['text.latex.preamble'] = (

r'\PassOptionsToPackage{dvipsnames}{xcolor}\usepackage{%s}' % pkg)

fig = plt.figure()

text2 = fig.text(0.5, 0.5, "Some text 0123456789")

fig.canvas.draw()

np.testing.assert_array_equal(text2.get_window_extent(),

text.get_window_extent())

@pytest.mark.parametrize(

"preamble",

[r"\usepackage[full]{textcomp}", r"\usepackage{underscore}"],

)

def test_latex_pkg_already_loaded(preamble):

plt.rcParams["text.latex.preamble"] = preamble

fig = plt.figure()

fig.text(.5, .5, "hello, world", usetex=True)

fig.canvas.draw()

def test_usetex_with_underscore():

plt.rcParams["text.usetex"] = True

df = {"a_b": range(5)[::-1], "c": range(5)}

fig, ax = plt.subplots()

ax.plot("c", "a_b", data=df)

ax.legend()

ax.text(0, 0, "foo_bar", usetex=True)

plt.draw()

@pytest.mark.flaky(reruns=3) # Tends to hit a TeX cache lock on AppVeyor.

@pytest.mark.parametrize("fmt", ["pdf", "svg"])

def test_missing_psfont(fmt, monkeypatch):

"""An error is raised if a TeX font lacks a Type-1 equivalent"""

monkeypatch.setattr(

dviread.PsfontsMap, '__getitem__',

lambda self, k: dviread.PsFont(

texname=b'texfont', psname=b'Some Font',

effects=None, encoding=None, filename=None))

mpl.rcParams['text.usetex'] = True

fig, ax = plt.subplots()

ax.text(0.5, 0.5, 'hello')

with TemporaryFile() as tmpfile, pytest.raises(ValueError):

fig.savefig(tmpfile, format=fmt)

def test_pdf_type1_font_subsetting():

"""Test that fonts in PDF output are properly subset."""

pikepdf = pytest.importorskip("pikepdf")

mpl.rcParams["text.usetex"] = True

mpl.rcParams["text.latex.preamble"] = r"\usepackage{amssymb}"

fig, ax = plt.subplots()

ax.text(0.2, 0.7, r"$\int_{-\infty}^{\aleph}\sqrt{\alpha\beta\gamma}\mathrm{d}x$")

ax.text(0.2, 0.5, r"$\mathfrak{x}\circledcirc\mathfrak{y}\in\mathbb{R}$")

with TemporaryFile() as tmpfile:

fig.savefig(tmpfile, format="pdf")

tmpfile.seek(0)

pdf = pikepdf.Pdf.open(tmpfile)

length = {}

page = pdf.pages[0]

for font_name, font in page.Resources.Font.items():

assert font.Subtype == "/Type1", (

f"Font {font_name}={font} is not a Type 1 font"

)

# Subsetted font names have a 6-character tag followed by a '+'

base_font = str(font["/BaseFont"]).removeprefix("/")

assert re.match(r"^[A-Z]{6}\+", base_font), (

f"Font {font_name}={base_font} lacks a subset indicator tag"

)

assert "/FontFile" in font.FontDescriptor, (

f"Type 1 font {font_name}={base_font} is not embedded"

)

_, original_name = base_font.split("+", 1)

length[original_name] = len(bytes(font["/FontDescriptor"]["/FontFile"]))

print("Embedded font stream lengths:", length)

# We should have several fonts, each much smaller than the original.

# I get under 10kB on my system for each font, but allow 15kB in case

# of differences in the font files.

assert {

'CMEX10',

'CMMI12',

'CMR12',

'CMSY10',

'CMSY8',

'EUFM10',

'MSAM10',

'MSBM10',

}.issubset(length), "Missing expected fonts in the PDF"

for font_name, length in length.items():

assert length < 15_000, (

f"Font {font_name}={length} is larger than expected"

)

# For comparison, lengths without subsetting on my system:

# 'CMEX10': 29686

# 'CMMI12': 36176

# 'CMR12': 32157

# 'CMSY10': 32004

# 'CMSY8': 32061

# 'EUFM10': 20546

# 'MSAM10': 31199

# 'MSBM10': 34129

try:

_old_gs_version = mpl._get_executable_info('gs').version < parse_version('9.55')

except mpl.ExecutableNotFoundError:

_old_gs_version = True

@image_comparison(baseline_images=['rotation'], extensions=['eps', 'pdf', 'png', 'svg'],

style='mpl20', tol=3.91 if _old_gs_version else 0)

def test_rotation():

mpl.rcParams['text.usetex'] = True

fig = plt.figure()

ax = fig.add_axes((0, 0, 1, 1))

ax.set(xlim=(-0.5, 5), xticks=[], ylim=(-0.5, 3), yticks=[], frame_on=False)

text = {val: val[0] for val in ['top', 'center', 'bottom', 'left', 'right']}

text['baseline'] = 'B'

text['center_baseline'] = 'C'

for i, va in enumerate(['top', 'center', 'bottom', 'baseline', 'center_baseline']):

for j, ha in enumerate(['left', 'center', 'right']):

for k, angle in enumerate([0, 90, 180, 270]):

k //= 2

x = i + k / 2

y = j + k / 2

ax.plot(x, y, '+', c=f'C{k}', markersize=20, markeredgewidth=0.5)

# 'My' checks full height letters plus descenders.

ax.text(x, y, f"$\\mathrm{{My {text[ha]}{text[va]} {angle}}}$",

rotation=angle, horizontalalignment=ha, verticalalignment=va)

def test_unicode_sizing():

tp = mpl.textpath.TextToPath()

scale1 = tp.get_glyphs_tex(mpl.font_manager.FontProperties(), "W")[0][0][3]

scale2 = tp.get_glyphs_tex(mpl.font_manager.FontProperties(), r"\textwon")[0][0][3]

assert scale1 == scale2