pyllint: enable consider-user-enumerate

This caught a couple of cases of us doing:
```python
for i in range(len(x)):
   v = x[i]
```
which are places to use enumerate instead.

It also caught a couple of cases of:
```python
assert len(x) == len(y)
for i in range(len(x)):
    xv = x[i]
    yv = y[i]
```
Which should instead be using zip()
```python
for xv, yv in zip(x, y):
    ...
```

.pylintrc

@@ -13,6 +13,7 @@ enable=
     bare-except,
     compare-to-zero,
     consider-iterating-dictionary,
+    consider-using-enumerate,
     dangerous-default-value,
     deprecated-lambda,
     len-as-condition,

mesonbuild/backend/ninjabackend.py

@@ -2193,8 +2193,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         infilelist = genlist.get_inputs()
         outfilelist = genlist.get_outputs()
         extra_dependencies = self.get_custom_target_depend_files(genlist)
-        for i in range(len(infilelist)):
-            curfile = infilelist[i]
+        for i, curfile in enumerate(infilelist):
             if len(generator.outputs) == 1:
                 sole_output = os.path.join(self.get_target_private_dir(target), outfilelist[i])
             else:

mesonbuild/backend/vs2010backend.py

@@ -122,12 +122,11 @@ class Vs2010Backend(backends.Backend):
                 source_dir = os.path.join(down, self.build_to_src, genlist.subdir)
                 exe_arr = self.build_target_to_cmd_array(exe)
                 idgroup = ET.SubElement(parent_node, 'ItemGroup')
-                for i in range(len(infilelist)):
+                for i, curfile in enumerate(infilelist):
                     if len(infilelist) == len(outfilelist):
                         sole_output = os.path.join(target_private_dir, outfilelist[i])
                     else:
                         sole_output = ''
-                    curfile = infilelist[i]
                     infilename = os.path.join(down, curfile.rel_to_builddir(self.build_to_src))
                     deps = self.get_custom_target_depend_files(genlist, True)
                     base_args = generator.get_arglist(infilename)

mesonbuild/backend/xcodebackend.py

@@ -678,9 +678,7 @@ class XCodeBackend(backends.Backend):
         file_ids = self.generator_buildfile_ids[(tname, generator_id)]
         ref_ids = self.generator_fileref_ids[(tname, generator_id)]
         assert len(ref_ids) == len(file_ids)
-        for i in range(len(file_ids)):
-            file_o = file_ids[i]
-            ref_id = ref_ids[i]
+        for file_o, ref_id in zip(file_ids, ref_ids):
             odict = PbxDict()
             objects_dict.add_item(file_o, odict)
             odict.add_item('isa', 'PBXBuildFile')
@@ -758,9 +756,7 @@ class XCodeBackend(backends.Backend):
                 outputs = self.generator_outputs[(tname, generator_id)]
                 ref_ids = self.generator_fileref_ids[tname, generator_id]
                 assert len(ref_ids) == len(outputs)
-                for i in range(len(outputs)):
-                    o = outputs[i]
-                    ref_id = ref_ids[i]
+                for o, ref_id in zip(outputs, ref_ids):
                     odict = PbxDict()
                     name = os.path.basename(o)
                     objects_dict.add_item(ref_id, odict, o)