Trac #16086: Python 3 preparation: Py2 vs. Py3 return value of write(…

…) in doctests

The write() function does return nothing in Py2
{{{
>>> sys.version
'2.7.5+ (default, Feb 27 2014, 19:37:08) \n[GCC 4.8.1]'
>>> with open("tracked", "w") as f: f.write("boo")
...
>>>
}}}
while in Py3 it returns the number of bytes written
{{{
>>> sys.version
'3.3.2+ (default, Feb 28 2014, 00:52:16) \n[GCC 4.8.1]'
>>> with open("tracked", "w") as f: f.write("boo")
...
3
>>>
}}}
This can be unified by adding something like {{{ignore =}}}
{{{
>>> sys.version
'3.3.2+ (default, Feb 28 2014, 00:52:16) \n[GCC 4.8.1]'
>>> with open("tracked", "w") as f: ignore = f.write("boo")
...
>>>
}}}
About 79 py module are effected.

This ticket is tracked as a dependency of meta-ticket ticket:16052.

URL: https://trac.sagemath.org/16086
Reported by: wluebbe
Ticket author(s): John Palmieri
Reviewer(s): Travis Scrimshaw

src/sage/doctest/control.py

@@ -170,7 +170,7 @@ def skipfile(filename):
         sage: f = tmp_filename(ext=".pyx")
         sage: skipfile(f)
         False
-        sage: open(f, "w").write("# nodoctest")
+        sage: _ = open(f, "w").write("# nodoctest")
         sage: skipfile(f)
         True
     """
@@ -198,7 +198,7 @@ class Logger(object):
         sage: from sage.doctest.control import Logger
         sage: t = open(tmp_filename(), "w+")
         sage: L = Logger(sys.stdout, t)
-        sage: L.write("hello world\n")
+        sage: _ = L.write("hello world\n")
         hello world
         sage: t.seek(0)
         sage: t.read()
@@ -707,7 +707,7 @@ def expand_files_into_sources(self):
             sage: dirname = tmp_dir()
             sage: filename = os.path.join(dirname, 'not_tested.py')
             sage: with open(filename, 'w') as F:
-            ....:     F.write("#"*80 + "\n\n\n\n## nodoctest\n    sage: 1+1\n    4")
+            ....:     _ = F.write("#"*80 + "\n\n\n\n## nodoctest\n    sage: 1+1\n    4")
             sage: DC = DocTestController(DD, [dirname])
             sage: DC.expand_files_into_sources()
             sage: DC.sources

src/sage/doctest/sources.py

@@ -509,7 +509,7 @@ def __iter__(self):
             sage: from sage.doctest.sources import FileDocTestSource
             sage: filename = tmp_filename(ext=".py")
             sage: s = "'''\n    sage: 2 + 2\n    4\n'''"
-            sage: open(filename, 'w').write(s)
+            sage: _ = open(filename, 'w').write(s)
             sage: FDS = FileDocTestSource(filename, DocTestDefaults())
             sage: for n, line in FDS:
             ....:     print("{} {}".format(n, line))

src/sage/finance/stock.py

@@ -521,7 +521,7 @@ def load_from_file(self, file):
         object like so. Note that the path must be explicit::
 
             sage: filename = tmp_filename(ext='.csv')
-            sage: open(filename,'w').write("Date,Open,High,Low,Close,Volume\n1212405780,187.80,187.80,187.80,187.80,100\n1212407640,187.75,188.00,187.75,188.00,2000\n1212407700,188.00,188.00,188.00,188.00,1000\n1212408000,188.00,188.11,188.00,188.00,2877\n1212408060,188.00,188.00,188.00,188.00,687")
+            sage: _ = open(filename,'w').write("Date,Open,High,Low,Close,Volume\n1212405780,187.80,187.80,187.80,187.80,100\n1212407640,187.75,188.00,187.75,188.00,2000\n1212407700,188.00,188.00,188.00,188.00,1000\n1212408000,188.00,188.11,188.00,188.00,2877\n1212408060,188.00,188.00,188.00,188.00,687")
             sage: finance.Stock('aapl').load_from_file(filename)[:5]
             [
             1212408060 188.00 188.00 188.00 188.00        687,
@@ -568,7 +568,7 @@ def _load_from_csv(self, R):
         This indirectly tests ``_load_from_csv()``::
 
             sage: filename = tmp_filename(ext='.csv')
-            sage: open(filename,'w').write("Date,Open,High,Low,Close,Volume\n1212405780,187.80,187.80,187.80,187.80,100\n1212407640,187.75,188.00,187.75,188.00,2000\n1212407700,188.00,188.00,188.00,188.00,1000\n1212408000,188.00,188.11,188.00,188.00,2877\n1212408060,188.00,188.00,188.00,188.00,687")
+            sage: _ = open(filename,'w').write("Date,Open,High,Low,Close,Volume\n1212405780,187.80,187.80,187.80,187.80,100\n1212407640,187.75,188.00,187.75,188.00,2000\n1212407700,188.00,188.00,188.00,188.00,1000\n1212408000,188.00,188.11,188.00,188.00,2877\n1212408060,188.00,188.00,188.00,188.00,687")
             sage: finance.Stock('aapl').load_from_file(filename)
             [
             1212408060 188.00 188.00 188.00 188.00        687,

src/sage/game_theory/parser.py

@@ -143,9 +143,9 @@ def format_lrs(self):
             sage: g2_name = tmp_filename()
             sage: g1_file = open(g1_name, 'w')
             sage: g2_file = open(g2_name, 'w')
-            sage: g1_file.write(game1_str)
+            sage: _ = g1_file.write(game1_str)
             sage: g1_file.close()
-            sage: g2_file.write(game2_str)
+            sage: _ = g2_file.write(game2_str)
             sage: g2_file.close()
             sage: process = Popen(['lrsnash', g1_name, g2_name], stdout=PIPE, stderr=PIPE)  # optional - lrslib
             sage: lrs_output = [row for row in process.stdout]  # optional - lrslib
@@ -188,9 +188,9 @@ def format_lrs(self):
             sage: g2_name = tmp_filename()
             sage: g1_file = open(g1_name, 'w')
             sage: g2_file = open(g2_name, 'w')
-            sage: g1_file.write(game1_str)
+            sage: _ = g1_file.write(game1_str)
             sage: g1_file.close()
-            sage: g2_file.write(game2_str)
+            sage: _ = g2_file.write(game2_str)
             sage: g2_file.close()
             sage: process = Popen(['lrsnash', g1_name, g2_name], stdout=PIPE, stderr=PIPE)  # optional - lrslib
             sage: lrs_output = [row for row in process.stdout]  # optional - lrslib

src/sage/geometry/polyhedron/plot.py

@@ -1315,7 +1315,7 @@ def tikz(self, view=[0, 0, 1], angle=0, scale=2,
                 [x={(-0.939161cm, 0.244762cm)},
                 y={(0.097442cm, -0.482887cm)},
                 z={(0.329367cm, 0.840780cm)},
-            sage: open('polytope-tikz1.tex', 'w').write(Image1)    # not tested
+            sage: _ = open('polytope-tikz1.tex', 'w').write(Image1)    # not tested
 
             sage: P2 = Polyhedron(vertices=[[1, 1],[1, 2],[2, 1]])
             sage: Image2 = P2.projection().tikz(scale=3, edge_color='blue!95!black', facet_color='orange!95!black', opacity=0.4, vertex_color='yellow', axis=True)
@@ -1326,7 +1326,7 @@ def tikz(self, view=[0, 0, 1], angle=0, scale=2,
                 [scale=3.000000,
                 back/.style={loosely dotted, thin},
                 edge/.style={color=blue!95!black, thick},
-            sage: open('polytope-tikz2.tex', 'w').write(Image2)    # not tested
+            sage: _ = open('polytope-tikz2.tex', 'w').write(Image2)    # not tested
 
             sage: P3 = Polyhedron(vertices=[[-1, -1, 2],[-1, 2, -1],[2, -1, -1]])
             sage: P3
@@ -1337,7 +1337,7 @@ def tikz(self, view=[0, 0, 1], angle=0, scale=2,
                 [x={(0.658184cm, -0.242192cm)},
                 y={(-0.096240cm, 0.912008cm)},
                 z={(-0.746680cm, -0.331036cm)},
-            sage: open('polytope-tikz3.tex', 'w').write(Image3)    # not tested
+            sage: _ = open('polytope-tikz3.tex', 'w').write(Image3)    # not tested
 
             sage: P=Polyhedron(vertices=[[1,1,0,0],[1,2,0,0],[2,1,0,0],[0,0,1,0],[0,0,0,1]])
             sage: P
@@ -1408,7 +1408,7 @@ def _tikz_2d(self, scale, edge_color, facet_color, opacity, vertex_color, axis):
                 [scale=3.000000,
                 back/.style={loosely dotted, thin},
                 edge/.style={color=black, thick},
-            sage: open('polytope-tikz2.tex', 'w').write(Image)    # not tested
+            sage: _ = open('polytope-tikz2.tex', 'w').write(Image)    # not tested
 
 
         Scientific notation is not used in the output (:trac:`16519`)::
@@ -1526,7 +1526,7 @@ def _tikz_2d_in_3d(self, view, angle, scale, edge_color, facet_color,
                 [x={(0.644647cm, -0.476559cm)},
                 y={(0.192276cm, 0.857859cm)},
                 z={(-0.739905cm, -0.192276cm)},
-            sage: open('polytope-tikz3.tex', 'w').write(Image)    # not tested
+            sage: _ open('polytope-tikz3.tex', 'w').write(Image)    # not tested
 
             sage: p = Polyhedron(vertices=[[1,0,0],[0,1,0],[0,0,1]])
             sage: proj = p.projection()
@@ -1654,7 +1654,7 @@ def _tikz_3d_in_3d(self, view, angle, scale, edge_color,
                 [x={(-0.046385cm, 0.837431cm)},
                 y={(-0.243536cm, 0.519228cm)},
                 z={(0.968782cm, 0.170622cm)},
-            sage: open('polytope-tikz1.tex', 'w').write(Image)    # not tested
+            sage: _ = open('polytope-tikz1.tex', 'w').write(Image)    # not tested
 
             sage: Associahedron = Polyhedron(vertices=[[1,0,1],[1,0,0],[1,1,0],[0,0,-1],[0,1,0],[-1,0,0],[0,1,1],[0,0,1],[0,-1,0]]).polar()
             sage: ImageAsso = Associahedron.projection().tikz([-15,-755,-655], 116, scale=1)

src/sage/graphs/bipartite_graph.py

@@ -207,10 +207,10 @@ class BipartiteGraph(Graph):
 
          sage: file_name = os.path.join(SAGE_TMP, 'deleteme.alist.txt')
          sage: fi = open(file_name, 'w')
-         sage: fi.write("7 4 \n 3 4 \n 3 3 1 3 1 1 1 \n 3 3 3 4 \n\
-                         1 2 4 \n 1 3 4 \n 1 0 0 \n 2 3 4 \n\
-                         2 0 0 \n 3 0 0 \n 4 0 0 \n\
-                         1 2 3 0 \n 1 4 5 0 \n 2 4 6 0 \n 1 2 4 7 \n")
+         sage: _ = fi.write("7 4 \n 3 4 \n 3 3 1 3 1 1 1 \n 3 3 3 4 \n\
+                             1 2 4 \n 1 3 4 \n 1 0 0 \n 2 3 4 \n\
+                             2 0 0 \n 3 0 0 \n 4 0 0 \n\
+                             1 2 3 0 \n 1 4 5 0 \n 2 4 6 0 \n 1 2 4 7 \n")
          sage: fi.close();
          sage: B = BipartiteGraph(file_name)
          sage: B == H
@@ -998,10 +998,10 @@ def load_afile(self, fname):
 
             sage: file_name = os.path.join(SAGE_TMP, 'deleteme.alist.txt')
             sage: fi = open(file_name, 'w')
-            sage: fi.write("7 4 \n 3 4 \n 3 3 1 3 1 1 1 \n 3 3 3 4 \n\
-                            1 2 4 \n 1 3 4 \n 1 0 0 \n 2 3 4 \n\
-                            2 0 0 \n 3 0 0 \n 4 0 0 \n\
-                            1 2 3 0 \n 1 4 5 0 \n 2 4 6 0 \n 1 2 4 7 \n")
+            sage: _ = fi.write("7 4 \n 3 4 \n 3 3 1 3 1 1 1 \n 3 3 3 4 \n\
+                                1 2 4 \n 1 3 4 \n 1 0 0 \n 2 3 4 \n\
+                                2 0 0 \n 3 0 0 \n 4 0 0 \n\
+                                1 2 3 0 \n 1 4 5 0 \n 2 4 6 0 \n 1 2 4 7 \n")
             sage: fi.close();
             sage: B = BipartiteGraph()
             sage: B.load_afile(file_name)

src/sage/graphs/generic_graph.py

@@ -19659,7 +19659,7 @@ def graphviz_to_file_named(self, filename, **options):
               node_2 -- node_3 [label="foo"];
             }
         """
-        return open(filename, 'wt').write(self.graphviz_string(**options))
+        open(filename, 'wt').write(self.graphviz_string(**options))
 
     ### Spectrum
 

src/sage/graphs/graph_generators.py

@@ -1048,9 +1048,9 @@ def _read_planar_code(self, code_input):
 
             sage: from six import StringIO
             sage: code_input = StringIO('>>planar_code<<')
-            sage: code_input.write('>>planar_code<<')
+            sage: _ = code_input.write('>>planar_code<<')
             sage: for c in [4,2,3,4,0,1,4,3,0,1,2,4,0,1,3,2,0]:
-            ....:     code_input.write('{:c}'.format(c))
+            ....:     _ = code_input.write('{:c}'.format(c))
             sage: code_input.seek(0)
             sage: gen = graphs._read_planar_code(code_input)
             sage: l = list(gen)

src/sage/interfaces/axiom.py

@@ -262,7 +262,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename(ext='.input')
             sage: f = open(filename, 'w')
-            sage: f.write('xx := 22;\n')
+            sage: _ = f.write('xx := 22;\n')
             sage: f.close()
             sage: axiom.read(filename)    # optional - axiom
             sage: axiom.get('xx')         # optional - axiom

src/sage/interfaces/gap.py

@@ -477,7 +477,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('xx := 22;\n')
+            sage: _ = f.write('xx := 22;\n')
             sage: f.close()
             sage: gap.read(filename)
             sage: gap.get('xx').strip()

src/sage/interfaces/giac.py

@@ -372,7 +372,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename,'w')
-            sage: f.write('xx := 22;\n')
+            sage: _ = f.write('xx := 22;\n')
             sage: f.close()
             sage: giac.read(filename)
             sage: giac.get('xx').strip()

src/sage/interfaces/gp.py

@@ -328,7 +328,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('x = 22;\n')
+            sage: _ = f.write('x = 22;\n')
             sage: f.close()
             sage: gp.read(filename)
             sage: gp.get('x').strip()

src/sage/interfaces/interface.py

@@ -185,7 +185,7 @@ def read(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('x = 2\n')
+            sage: _ = f.write('x = 2\n')
             sage: f.close()
             sage: octave.read(filename)  # optional - octave
             sage: octave.get('x')        # optional - octave

src/sage/interfaces/lie.py

@@ -554,7 +554,7 @@ def read(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('x = 2\n')
+            sage: _ = f.write('x = 2\n')
             sage: f.close()
             sage: lie.read(filename)  # optional - lie
             sage: lie.get('x')        # optional - lie

src/sage/interfaces/macaulay2.py

@@ -231,7 +231,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, "w")
-            sage: f.write("sage_test = 7;")
+            sage: _ = f.write("sage_test = 7;")
             sage: f.close()
             sage: command = macaulay2._read_in_file_command(filename)
             sage: macaulay2.eval(command)  # optional - macaulay2

src/sage/interfaces/magma.py

@@ -1044,7 +1044,7 @@ def load(self, filename):
         EXAMPLES::
 
             sage: filename = os.path.join(SAGE_TMP, 'a.m')
-            sage: open(filename, 'w').write('function f(n) return n^2; end function;\nprint "hi";')
+            sage: _ = open(filename, 'w').write('function f(n) return n^2; end function;\nprint "hi";')
             sage: print(magma.load(filename))      # optional - magma
             Loading ".../a.m"
             hi

src/sage/interfaces/maple.py

@@ -360,7 +360,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()  # optional - maple
             sage: f = open(filename, 'w')  # optional - maple
-            sage: f.write('xx := 22;\n')  # optional - maple
+            sage: _ = f.write('xx := 22;\n')  # optional - maple
             sage: f.close()               # optional - maple
             sage: maple.read(filename)    # optional - maple
             sage: maple.get('xx').strip() # optional - maple

src/sage/interfaces/mupad.py

@@ -166,7 +166,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('x := 2;\n')
+            sage: _ = f.write('x := 2;\n')
             sage: f.close()
             sage: mupad.read(filename)   # optional - MuPAD
             sage: mupad.get('x').strip() # optional - mupad

src/sage/interfaces/r.py

@@ -567,7 +567,7 @@ def read(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('a <- 2+2\n')
+            sage: _ = f.write('a <- 2+2\n')
             sage: f.close()
             sage: r.read(filename)
             sage: r.get('a')

src/sage/interfaces/read_data.py

@@ -28,12 +28,12 @@ def read_data(f,t):
 
        sage: indata = tmp_filename()
        sage: f = open(indata, "w")
-       sage: f.write("17\n42\n")
+       sage: _ = f.write("17\n42\n")
        sage: f.close()
        sage: l = read_data(indata, ZZ); l
        [17, 42]
        sage: f = open(indata, "w")
-       sage: f.write("1.234\n5.678\n")
+       sage: _ = f.write("1.234\n5.678\n")
        sage: f.close()
        sage: l = read_data(indata, RealField(17)); l
        [1.234, 5.678]

src/sage/interfaces/singular.py

@@ -538,7 +538,7 @@ def _read_in_file_command(self, filename):
 
             sage: filename = tmp_filename()
             sage: f = open(filename, 'w')
-            sage: f.write('int x = 2;\n')
+            sage: _ = f.write('int x = 2;\n')
             sage: f.close()
             sage: singular.read(filename)
             sage: singular.get('x')

src/sage/libs/eclib/mwrank.pyx

@@ -128,7 +128,7 @@ def initprimes(filename, verb=False):
     EXAMPLES::
 
         sage: file = os.path.join(SAGE_TMP, 'PRIMES')
-        sage: open(file,'w').write(' '.join([str(p) for p in prime_range(10^7,10^7+20)]))
+        sage: _ = open(file,'w').write(' '.join([str(p) for p in prime_range(10^7,10^7+20)]))
         sage: mwrank_initprimes(file, verb=True)
         Computed 78519 primes, largest is 1000253
         reading primes from file ...

src/sage/libs/pari/tests.py

@@ -181,10 +181,10 @@
 
     sage: import tempfile
     sage: gpfile = tempfile.NamedTemporaryFile(mode="w")
-    sage: gpfile.file.write("mysquare(n) = {\n")
-    sage: gpfile.file.write("    n^2;\n")
-    sage: gpfile.file.write("}\n")
-    sage: gpfile.file.write("polcyclo(5)\n")
+    sage: __ = gpfile.file.write("mysquare(n) = {\n")
+    sage: __ = gpfile.file.write("    n^2;\n")
+    sage: __ = gpfile.file.write("}\n")
+    sage: __ = gpfile.file.write("polcyclo(5)\n")
     sage: gpfile.file.flush()
     sage: pari.read(gpfile.name)
     x^4 + x^3 + x^2 + x + 1

src/sage/misc/cython.py

@@ -381,7 +381,7 @@ def cython(filename, verbose=False, compile_message=False,
         sage: d = sage.misc.temporary_file.tmp_dir()
         sage: os.chdir(d)
         sage: with open("test.pyx", 'w') as f:
-        ....:     f.write("#clang C++\n"
+        ....:     _ = f.write("#clang C++\n"
         ....:       "from libcpp.vector cimport vector\n"
         ....:       "cdef vector[int] * v = new vector[int](4)\n")
         sage: output = sage.misc.cython.cython("test.pyx", create_local_c_file=True)
@@ -721,7 +721,7 @@ def cython_create_local_so(filename):
         sage: dir = tmp_dir(); os.chdir(dir)
         sage: f = open('hello.spyx', 'w')
         sage: s = "def hello():\n    print('hello')\n"
-        sage: f.write(s)
+        sage: _ = f.write(s)
         sage: f.close()
         sage: cython_create_local_so('hello.spyx')
         Compiling hello.spyx...

src/sage/misc/latex.py

@@ -690,7 +690,7 @@ def _run_latex_(filename, debug=False, density=150, engine=None, png=False, do_i
         sage: from sage.misc.latex import _run_latex_, _latex_file_
         sage: file = os.path.join(SAGE_TMP, "temp.tex")
         sage: O = open(file, 'w')
-        sage: O.write(_latex_file_([ZZ['x'], RR])); O.close()
+        sage: _ = O.write(_latex_file_([ZZ['x'], RR])); O.close()
         sage: _run_latex_(file) # random - depends on whether latex is installed
         'dvi'
     """
@@ -2150,7 +2150,7 @@ def view(objects, title='Sage', debug=False, sep='', tiny=False,
         sage: g = sage.misc.latex.latex_examples.graph()
         sage: latex.add_to_preamble(r"\usepackage{tkz-graph}")
         sage: file = os.path.join(SAGE_TMP, "temp.tex")
-        sage: O = open(file, 'w'); O.write(_latex_file_(g)); O.close()
+        sage: O = open(file, 'w'); _ = O.write(_latex_file_(g)); O.close()
         sage: _run_latex_(file, engine="pdflatex") # optional - latex
         'pdf'
 

src/sage/misc/reset.pyx

@@ -39,7 +39,7 @@ def reset(vars=None, attached=False):
 
         sage: fn = tmp_filename(ext='foo.py')
         sage: sage.misc.reset.EXCLUDE.add('fn')
-        sage: open(fn, 'w').write('a = 111')
+        sage: _ = open(fn, 'w').write('a = 111')
         sage: attach(fn)
         sage: [fn] == attached_files()
         True