check-code: make repquote distinguish more characters for exact detection

This patch makes repquote() distinguish more characters below, as a
preparation for exact detection in subsequent patch.

  - "%"  as "%"
  - "\\" as "b"(ackslash)
  - "*"  as "A"(sterisk)
  - "+"  as "P"(lus)
  - "-"  as "M"(inus)

Characters other than "%" don't use itself as replacement, because
they are treated as special ones in regexp.

contrib/check-code.py

@@ -53,7 +53,8 b' def compilere(pat, multiline=False):'
 def repquote(m):
     # check "rules depending on implementation of repquote()" in each
     # patterns (especially pypats), before changing this function
-    fixedmap = {' ': ' ', '\n': '\n', '.': 'p', ':': 'q'}
+    fixedmap = {' ': ' ', '\n': '\n', '.': 'p', ':': 'q',
+                '%': '%', '\\': 'b', '*': 'A', '+': 'P', '-': 'M'}
     def encodechr(i):
         if i > 255:
             return 'u'
@@ -326,7 +327,8 b' pypats = ['
     (r'\.next\(\)', "don't use .next(), use next(...)"),
 
     # rules depending on implementation of repquote()
-    (r' x+[xpqo][\'"]\n\s+[\'"]x', 'string join across lines with no space'),
+    (r' x+[xpqo%APM][\'"]\n\s+[\'"]x',
+     'string join across lines with no space'),
     (r'ui\.(status|progress|write|note|warn)\([\'\"]x',
      "missing _() in ui message (use () to hide false-positives)"),
   ],

tests/test-contrib-check-code.t

@@ -256,6 +256,10 b' web templates'
   >        'bar foo.'
   >        'bar foo:'
   >        'bar foo@'
+  >        'bar foo%'
+  >        'bar foo*'
+  >        'bar foo+'
+  >        'bar foo-'
   >        'bar')
   > EOF
   $ "$check_code" stringjoin.py
@@ -271,4 +275,16 b' web templates'
   stringjoin.py:4:
    >        'bar foo@'
    string join across lines with no space
+  stringjoin.py:5:
+   >        'bar foo%'
+   string join across lines with no space
+  stringjoin.py:6:
+   >        'bar foo*'
+   string join across lines with no space
+  stringjoin.py:7:
+   >        'bar foo+'
+   string join across lines with no space
+  stringjoin.py:8:
+   >        'bar foo-'
+   string join across lines with no space
   [1]