MAINT: Migrate pyf.src from distutils [skip-ci]

numpy · tylerjereddy · Dec 1, 2023 · Nov 30, 2023 · Dec 1, 2023 · Dec 1, 2023
commit 6aceaa9b5535f4a69ec946c118ebf4ffee28806c
diff --git a/numpy/f2py/_src_pyf.py b/numpy/f2py/_src_pyf.py
@@ -0,0 +1,239 @@
+import re
+
+# START OF CODE VENDORED FROM `numpy.distutils.from_template`
+#############################################################
+"""
+process_file(filename)
+
+  takes templated file .xxx.src and produces .xxx file where .xxx
+  is .pyf .f90 or .f using the following template rules:
+
+  '<..>' denotes a template.
+
+  All function and subroutine blocks in a source file with names that
+  contain '<..>' will be replicated according to the rules in '<..>'.
+
+  The number of comma-separated words in '<..>' will determine the number of
+  replicates.
+
+  '<..>' may have two different forms, named and short. For example,
+
+  named:
+   <p=d,s,z,c> where anywhere inside a block '<p>' will be replaced with
+   'd', 's', 'z', and 'c' for each replicate of the block.
+
+   <_c>  is already defined: <_c=s,d,c,z>
+   <_t>  is already defined: <_t=real,double precision,complex,double complex>
+
+  short:
+   <s,d,c,z>, a short form of the named, useful when no <p> appears inside
+   a block.
+
+  In general, '<..>' contains a comma separated list of arbitrary
+  expressions. If these expression must contain a comma|leftarrow|rightarrow,
+  then prepend the comma|leftarrow|rightarrow with a backslash.
+
+  If an expression matches '\\<index>' then it will be replaced
+  by <index>-th expression.
+
+  Note that all '<..>' forms in a block must have the same number of
+  comma-separated entries.
+
+ Predefined named template rules:
+  <prefix=s,d,c,z>
+  <ftype=real,double precision,complex,double complex>
+  <ftypereal=real,double precision,\\0,\\1>
+  <ctype=float,double,complex_float,complex_double>
+  <ctypereal=float,double,\\0,\\1>
+"""
+
+routine_start_re = re.compile(r'(\n|\A)((     (\$|\*))|)\s*(subroutine|function)\b', re.I)
+routine_end_re = re.compile(r'\n\s*end\s*(subroutine|function)\b.*(\n|\Z)', re.I)
+function_start_re = re.compile(r'\n     (\$|\*)\s*function\b', re.I)
+
+def parse_structure(astr):
+    """ Return a list of tuples for each function or subroutine each
+    tuple is the start and end of a subroutine or function to be
+    expanded.
+    """
+
+    spanlist = []
+    ind = 0
+    while True:
+        m = routine_start_re.search(astr, ind)
+        if m is None:
+            break
+        start = m.start()
+        if function_start_re.match(astr, start, m.end()):
+            while True:
+                i = astr.rfind('\n', ind, start)
+                if i==-1:
+                    break
+                start = i
+                if astr[i:i+7]!='\n     $':
+                    break
+        start += 1
+        m = routine_end_re.search(astr, m.end())
+        ind = end = m and m.end()-1 or len(astr)
+        spanlist.append((start, end))
+    return spanlist
+
+template_re = re.compile(r"<\s*(\w[\w\d]*)\s*>")
+named_re = re.compile(r"<\s*(\w[\w\d]*)\s*=\s*(.*?)\s*>")
+list_re = re.compile(r"<\s*((.*?))\s*>")
+
+def find_repl_patterns(astr):
+    reps = named_re.findall(astr)
+    names = {}
+    for rep in reps:
+        name = rep[0].strip() or unique_key(names)
+        repl = rep[1].replace(r'\,', '@comma@')
+        thelist = conv(repl)
+        names[name] = thelist
+    return names
+
+def find_and_remove_repl_patterns(astr):
+    names = find_repl_patterns(astr)
+    astr = re.subn(named_re, '', astr)[0]
+    return astr, names
+
+item_re = re.compile(r"\A\\(?P<index>\d+)\Z")
+def conv(astr):
+    b = astr.split(',')
+    l = [x.strip() for x in b]
+    for i in range(len(l)):
+        m = item_re.match(l[i])
+        if m:
+            j = int(m.group('index'))
+            l[i] = l[j]
+    return ','.join(l)
+
+def unique_key(adict):
+    """ Obtain a unique key given a dictionary."""
+    allkeys = list(adict.keys())
+    done = False
+    n = 1
+    while not done:
+        newkey = '__l%s' % (n)
+        if newkey in allkeys:
+            n += 1
+        else:
+            done = True
+    return newkey
+
+
+template_name_re = re.compile(r'\A\s*(\w[\w\d]*)\s*\Z')
+def expand_sub(substr, names):
+    substr = substr.replace(r'\>', '@rightarrow@')
+    substr = substr.replace(r'\<', '@leftarrow@')
+    lnames = find_repl_patterns(substr)
+    substr = named_re.sub(r"<\1>", substr)  # get rid of definition templates
+
+    def listrepl(mobj):
+        thelist = conv(mobj.group(1).replace(r'\,', '@comma@'))
+        if template_name_re.match(thelist):
+            return "<%s>" % (thelist)
+        name = None
+        for key in lnames.keys():    # see if list is already in dictionary
+            if lnames[key] == thelist:
+                name = key
+        if name is None:      # this list is not in the dictionary yet
+            name = unique_key(lnames)
+            lnames[name] = thelist
+        return "<%s>" % name
+
+    substr = list_re.sub(listrepl, substr) # convert all lists to named templates
+                                           # newnames are constructed as needed
+
+    numsubs = None
+    base_rule = None
+    rules = {}
+    for r in template_re.findall(substr):
+        if r not in rules:
+            thelist = lnames.get(r, names.get(r, None))
+            if thelist is None:
+                raise ValueError('No replicates found for <%s>' % (r))
+            if r not in names and not thelist.startswith('_'):
+                names[r] = thelist
+            rule = [i.replace('@comma@', ',') for i in thelist.split(',')]
+            num = len(rule)
+
+            if numsubs is None:
+                numsubs = num
+                rules[r] = rule
+                base_rule = r
+            elif num == numsubs:
+                rules[r] = rule
+            else:
+                print("Mismatch in number of replacements (base <{}={}>) "
+                      "for <{}={}>. Ignoring.".format(base_rule, ','.join(rules[base_rule]), r, thelist))
+    if not rules:
+        return substr
+
+    def namerepl(mobj):
+        name = mobj.group(1)
+        return rules.get(name, (k+1)*[name])[k]
+
+    newstr = ''
+    for k in range(numsubs):
+        newstr += template_re.sub(namerepl, substr) + '\n\n'
+
+    newstr = newstr.replace('@rightarrow@', '>')
+    newstr = newstr.replace('@leftarrow@', '<')
+    return newstr
+
+def process_str(allstr):
+    newstr = allstr
+    writestr = ''
+
+    struct = parse_structure(newstr)
+
+    oldend = 0
+    names = {}
+    names.update(_special_names)
+    for sub in struct:
+        cleanedstr, defs = find_and_remove_repl_patterns(newstr[oldend:sub[0]])
+        writestr += cleanedstr
+        names.update(defs)
+        writestr += expand_sub(newstr[sub[0]:sub[1]], names)
+        oldend =  sub[1]
+    writestr += newstr[oldend:]
+
+    return writestr
+
+include_src_re = re.compile(r"(\n|\A)\s*include\s*['\"](?P<name>[\w\d./\\]+\.src)['\"]", re.I)
+
+def resolve_includes(source):
+    d = os.path.dirname(source)
+    with open(source) as fid:
+        lines = []
+        for line in fid:
+            m = include_src_re.match(line)
+            if m:
+                fn = m.group('name')
+                if not os.path.isabs(fn):
+                    fn = os.path.join(d, fn)
+                if os.path.isfile(fn):
+                    lines.extend(resolve_includes(fn))
+                else:
+                    lines.append(line)
+            else:
+                lines.append(line)
+    return lines
+
+def process_file(source):
+    lines = resolve_includes(source)
+    return process_str(''.join(lines))
+
+_special_names = find_repl_patterns('''
+<_c=s,d,c,z>
+<_t=real,double precision,complex,double complex>
+<prefix=s,d,c,z>
+<ftype=real,double precision,complex,double complex>
+<ctype=float,double,complex_float,complex_double>
+<ftypereal=real,double precision,\\0,\\1>
+<ctypereal=float,double,\\0,\\1>
+''')
+
+# END OF CODE VENDORED FROM `numpy.distutils.from_template`
+###########################################################
diff --git a/numpy/f2py/tests/test_pyf_src.py b/numpy/f2py/tests/test_pyf_src.py
@@ -0,0 +1,44 @@
+# This test is ported from numpy.distutils
+from numpy.f2py._src_pyf import process_str
+from numpy.testing import assert_equal
+
+
+pyf_src = """
+python module foo
+    <_rd=real,double precision>
+    interface
+        subroutine <s,d>foosub(tol)
+            <_rd>, intent(in,out) :: tol
+        end subroutine <s,d>foosub
+    end interface
+end python module foo
+"""
+
+expected_pyf = """
+python module foo
+    interface
+        subroutine sfoosub(tol)
+            real, intent(in,out) :: tol
+        end subroutine sfoosub
+        subroutine dfoosub(tol)
+            double precision, intent(in,out) :: tol
+        end subroutine dfoosub
+    end interface
+end python module foo
+"""
+
+
+def normalize_whitespace(s):
+    """
+    Remove leading and trailing whitespace, and convert internal
+    stretches of whitespace to a single space.
+    """
+    return ' '.join(s.split())
+
+
+def test_from_template():
+    """Regression test for gh-10712."""
+    pyf = process_str(pyf_src)
+    normalized_pyf = normalize_whitespace(pyf)
+    normalized_expected_pyf = normalize_whitespace(expected_pyf)
+    assert_equal(normalized_pyf, normalized_expected_pyf)