test_graph.py

# -*- coding: utf-8 -*-


import os
import subprocess
import shutil
import tempfile

from chempy import Reaction, ReactionSystem, Substance
from ..graph import rsys2dot, rsys2graph
from ..testing import requires, skipif

try:
    dot_missing = subprocess.run(["dot", "-?"]).returncode != 0
except OSError:
    dot_missing = True


def _get_rsys():
    r1 = Reaction({"A": 2}, {"B": 1}, param=3.0)
    A = Substance("A", latex_name="\\boldsymbol{A}")
    B = Substance("B", latex_name="\\boldsymbol{B}")
    rsys = ReactionSystem([r1], [A, B])
    return rsys


@requires("numpy")
@skipif(dot_missing, reason="graphviz not installed? (dot command missing)")
def test_rsys2dot():
    rsys = _get_rsys()
    assert list(map(str.strip, rsys2dot(rsys))) == [
        'digraph "None" {',
        '"A" [fontcolor=maroon label="A"];',
        '"B" [fontcolor=darkgreen label="B"];',
        "{",
        'node [label="r1",shape=diamond]',
        "r1",
        "}",
        '"A" -> "r1" [color=maroon,fontcolor=maroon,label="2"];',
        '"r1" -> "B" [color=darkgreen,fontcolor=darkgreen,label=""];',
        "}",
    ]


@requires("numpy")
@skipif(dot_missing, reason="graphviz not installed? (dot command missing)")
def test_rsys2graph():
    rsys = _get_rsys()
    tempdir = tempfile.mkdtemp()
    try:
        rsys2graph(rsys, os.path.join(tempdir, "out.png"))
        rsys2graph(rsys, os.path.join(tempdir, "out.ps"))
        try:
            subprocess.call(["dot2tex", "-v"])
        except Exception:
            pass
        else:
            rsys2graph(rsys, os.path.join(tempdir, "out.tex"))
    finally:
        shutil.rmtree(tempdir)