STY: Fix various style issues (#742)

.github/workflows/unit-tests.yaml

@@ -43,7 +43,7 @@ jobs:
 
     - name: Test with flake8
       run: |
-        flake8 . --ignore E,F,I,SIM,C,PT,N,ASS,A,P,R,W
+        flake8 . --ignore=E203,W503,E501,F405,E226,E128,E225,F403,E201,E202,E231,W504,E241,F401,E261,E302,E211,E701,E228,E111,F841,E117,E127,E251,E266,E
       if: matrix.python-version != '2.7'
 
     - name: Test with pytest

PyPDF2/filters.py

@@ -233,17 +233,17 @@ def decode(self):
             http://www.rasip.fer.hr/research/compress/algorithms/fund/lz/lzw.html
             and the PDFReference
             """
-            cW = self.CLEARDICT;
+            cW = self.CLEARDICT
             baos=""
             while True:
-                pW = cW;
-                cW = self.nextCode();
+                pW = cW
+                cW = self.nextCode()
                 if cW == -1:
                     raise PdfReadError("Missed the stop code in LZWDecode!")
                 if cW == self.STOP:
-                    break;
+                    break
                 elif cW == self.CLEARDICT:
-                    self.resetDict();
+                    self.resetDict()
                 elif pW == self.CLEARDICT:
                     baos+=self.dict[cW]
                 else:
@@ -255,7 +255,7 @@ def decode(self):
                     else:
                         p=self.dict[pW]+self.dict[pW][0]
                         baos+=p
-                        self.dict[self.dictlen] = p;
+                        self.dict[self.dictlen] = p
                         self.dictlen+=1
                     if (self.dictlen >= (1 << self.bitspercode) - 1 and
                         self.bitspercode < 12):
@@ -281,7 +281,7 @@ def decode(data, decodeParms=None):
                 if len(retval) == 0 and c == "<" and data[x+1] == "~":
                     x += 2
                     continue
-                #elif c.isspace():
+                # elif c.isspace():
                 #    x += 1
                 #    continue
                 elif c == 'z':

PyPDF2/generic.py

@@ -91,7 +91,7 @@ def readObject(stream, pdf):
         # number object OR indirect reference
         peek = stream.read(20)
         stream.seek(-len(peek), 1) # reset to start
-        if IndirectPattern.match(peek) != None:
+        if IndirectPattern.match(peek) is not None:
             return IndirectObject.readFromStream(stream, pdf)
         else:
             return NumberObject.readFromStream(stream)
@@ -181,7 +181,7 @@ def __repr__(self):
 
     def __eq__(self, other):
         return (
-            other != None and
+            other is not None and
             isinstance(other, IndirectObject) and
             self.idnum == other.idnum and
             self.generation == other.generation and
@@ -529,7 +529,7 @@ def __getitem__(self, key):
     # return None if no metadata was found on the document root.
     def getXmpMetadata(self):
         metadata = self.get("/Metadata", None)
-        if metadata == None:
+        if metadata is None:
             return None
         metadata = metadata.getObject()
         from . import xmp
@@ -614,7 +614,7 @@ def readFromStream(stream, pdf):
                 stream.seek(t, 0)
             data["__streamdata__"] = stream.read(length)
             if debug: print("here")
-            #if debug: print(binascii.hexlify(data["__streamdata__"]))
+            # if debug: print(binascii.hexlify(data["__streamdata__"]))
             e = readNonWhitespace(stream)
             ndstream = stream.read(8)
             if (e + ndstream) != b_("endstream"):
@@ -631,7 +631,6 @@ def readFromStream(stream, pdf):
                     # we found it by looking back one character further.
                     data["__streamdata__"] = data["__streamdata__"][:-1]
                 else:
-                    if debug: print(("E", e, ndstream, debugging.toHex(end)))
                     stream.seek(pos, 0)
                     raise utils.PdfReadError("Unable to find 'endstream' marker after stream at byte %s." % utils.hexStr(stream.tell()))
         else:
@@ -706,9 +705,9 @@ def removeChild(self, child):
         cur = curRef.getObject()
         lastRef = self[NameObject('/Last')]
         last = lastRef.getObject()
-        while cur != None:
+        while cur is not None:
             if cur == childObj:
-                if prev == None:
+                if prev is None:
                     if NameObject('/Next') in cur:
                         # Removing first tree node
                         nextRef = cur[NameObject('/Next')]

PyPDF2/merger.py

@@ -135,7 +135,7 @@ def merge(self, position, fileobj, bookmark=None, pages=None, import_bookmarks=T
             pdfr._decryption_key = decryption_key
 
         # Find the range of pages to merge.
-        if pages == None:
+        if pages is None:
             pages = (0, pdfr.getNumPages())
         elif isinstance(pages, PageRange):
             pages = pages.indices(pdfr.getNumPages())
@@ -219,8 +219,8 @@ def write(self, fileobj):
         for page in self.pages:
             self.output.addPage(page.pagedata)
             page.out_pagedata = self.output.getReference(self.output._pages.getObject()["/Kids"][-1].getObject())
-            #idnum = self.output._objects.index(self.output._pages.getObject()["/Kids"][-1].getObject()) + 1
-            #page.out_pagedata = IndirectObject(idnum, 0, self.output)
+            # idnum = self.output._objects.index(self.output._pages.getObject()["/Kids"][-1].getObject()) + 1
+            # page.out_pagedata = IndirectObject(idnum, 0, self.output)
 
         # Once all pages are added, create bookmarks to point at those pages
         self._write_dests()
@@ -358,12 +358,12 @@ def _write_dests(self):
                         pageno = i
                         pdf = p.src
                         break
-            if pageno != None:
+            if pageno is not None:
                 self.output.addNamedDestinationObject(v)
 
     def _write_bookmarks(self, bookmarks=None, parent=None):
 
-        if bookmarks == None:
+        if bookmarks is None:
             bookmarks = self.bookmarks
 
         last_added = None
@@ -377,10 +377,10 @@ def _write_bookmarks(self, bookmarks=None, parent=None):
             if '/Page' in b:
                 for i, p in enumerate(self.pages):
                     if p.id == b['/Page']:
-                        #b[NameObject('/Page')] = p.out_pagedata
+                        # b[NameObject('/Page')] = p.out_pagedata
                         args = [NumberObject(p.id), NameObject(b['/Type'])]
-                        #nothing more to add
-                        #if b['/Type'] == '/Fit' or b['/Type'] == '/FitB'
+                        # nothing more to add
+                        # if b['/Type'] == '/Fit' or b['/Type'] == '/FitB'
                         if b['/Type'] == '/FitH' or b['/Type'] == '/FitBH':
                             if '/Top' in b and not isinstance(b['/Top'], NullObject):
                                 args.append(FloatObject(b['/Top']))
@@ -431,7 +431,7 @@ def _write_bookmarks(self, bookmarks=None, parent=None):
                         pageno = i
                         pdf = p.src
                         break
-            if pageno != None:
+            if pageno is not None:
                 del b['/Page'], b['/Type']
                 last_added = self.output.addBookmarkDict(b, parent)
 
@@ -447,13 +447,13 @@ def _associate_dests_to_pages(self, pages):
                 if np.getObject() == p.pagedata.getObject():
                     pageno = p.id
 
-            if pageno != None:
+            if pageno is not None:
                 nd[NameObject('/Page')] = NumberObject(pageno)
             else:
                 raise ValueError("Unresolved named destination '%s'" % (nd['/Title'],))
 
     def _associate_bookmarks_to_pages(self, pages, bookmarks=None):
-        if bookmarks == None:
+        if bookmarks is None:
             bookmarks = self.bookmarks
 
         for b in bookmarks:
@@ -471,13 +471,13 @@ def _associate_bookmarks_to_pages(self, pages, bookmarks=None):
                 if bp.getObject() == p.pagedata.getObject():
                     pageno = p.id
 
-            if pageno != None:
+            if pageno is not None:
                 b[NameObject('/Page')] = NumberObject(pageno)
             else:
                 raise ValueError("Unresolved bookmark '%s'" % (b['/Title'],))
 
     def findBookmark(self, bookmark, root=None):
-        if root == None:
+        if root is None:
             root = self.bookmarks
 
         for i, b in enumerate(root):
@@ -499,7 +499,7 @@ def addBookmark(self, title, pagenum, parent=None):
         :param parent: A reference to a parent bookmark to create nested
             bookmarks.
         """
-        if parent == None:
+        if parent is None:
             iloc = [len(self.bookmarks)-1]
         elif isinstance(parent, list):
             iloc = parent
@@ -508,7 +508,7 @@ def addBookmark(self, title, pagenum, parent=None):
 
         dest = Bookmark(TextStringObject(title), NumberObject(pagenum), NameObject('/FitH'), NumberObject(826))
 
-        if parent == None:
+        if parent is None:
             self.bookmarks.append(dest)
         else:
             bmparent = self.bookmarks

PyPDF2/pagerange.py

@@ -101,14 +101,14 @@ def to_slice(self):
     def __str__(self):
         """ A string like "1:2:3". """
         s = self._slice
-        if s.step == None:
-            if s.start != None  and  s.stop == s.start + 1:
+        if s.step is None:
+            if s.start is not None  and  s.stop == s.start + 1:
                 return str(s.start)
 
             indices = s.start, s.stop
         else:
             indices = s.start, s.stop, s.step
-        return ':'.join("" if i == None else str(i) for i in indices)
+        return ':'.join("" if i is None else str(i) for i in indices)
 
     def __repr__(self):
         """ A string like "PageRange('1:2:3')". """