More templite fiddling: use locals instead of ctx[] each time.

1 files changed, 41 insertions, 11 deletions

diff --git a/coverage/templite.py b/coverage/templite.py
index 2ca12fef..088d74f1 100644
--- a/coverage/templite.py
+++ b/coverage/templite.py
@@ -8,9 +8,9 @@ import re
 class CodeBuilder(object):
     """Build source code conveniently."""
 
-    def __init__(self):
+    def __init__(self, indent=0):
         self.code = []
-        self.indent_amount = 0
+        self.indent_amount = indent
 
     def add_line(self, line):
         """Add a line of source to the code.
@@ -22,6 +22,12 @@ class CodeBuilder(object):
         self.code.append(line)
         self.code.append("\n")
 
+    def add_section(self):
+        """Add a section, a sub-CodeBuilder."""
+        sect = CodeBuilder(self.indent_amount)
+        self.code.append(sect)
+        return sect
+
     def indent(self):
         """Increase the current indent for following lines."""
         self.indent_amount += 4
@@ -30,11 +36,14 @@ class CodeBuilder(object):
         """Decrease the current indent for following lines."""
         self.indent_amount -= 4
 
+    def __str__(self):
+        return "".join(str(c) for c in self.code)
+
     def get_function(self, fn_name):
         """Compile the code, and return the function `fn_name`."""
         assert self.indent_amount == 0
         g = {}
-        code_text = "".join(self.code)
+        code_text = str(self)
         exec(code_text, g)
         return g[fn_name]
 
@@ -75,13 +84,27 @@ class Templite(object):
             self.context.update(context)
 
         # We construct a function in source form, then compile it and hold onto
-        # it, and execute it to create the template output.
+        # it, and execute it to render the template.
         code = CodeBuilder()
 
         code.add_line("def render(ctx, dot):")
         code.indent()
+        vars_code = code.add_section()
+        self.all_vars = set()
+        self.loop_vars = set()
         code.add_line("result = []")
-        code.add_line("r = result.append")
+        code.add_line("a = result.append")
+        code.add_line("e = result.extend")
+        code.add_line("s = str")
+
+        buffered = []
+        def flush_output():
+            """Force `buffered` to the code builder."""
+            if len(buffered) == 1:
+                code.add_line("a(%s)" % buffered[0])
+            elif len(buffered) > 1:
+                code.add_line("e([%s])" % ",".join(buffered))
+            del buffered[:]
 
         # Split the text to form a list of tokens.
         toks = re.split(r"(?s)({{.*?}}|{%.*?%}|{#.*?#})", text)
@@ -90,12 +113,13 @@ class Templite(object):
         for tok in toks:
             if tok.startswith('{{'):
                 # An expression to evaluate.
-                code.add_line("r(str(%s))" % self.expr_code(tok[2:-2].strip()))
+                buffered.append("s(%s)" % self.expr_code(tok[2:-2].strip()))
             elif tok.startswith('{#'):
                 # Comment: ignore it and move on.
                 continue
             elif tok.startswith('{%'):
                 # Action tag: split into words and parse further.
+                flush_output()
                 words = tok[2:-2].strip().split()
                 if words[0] == 'if':
                     # An if statement: evaluate the expression to determine if.
@@ -107,8 +131,9 @@ class Templite(object):
                     # A loop: iterate over expression result.
                     assert len(words) == 4 and words[2] == 'in'
                     ops_stack.append('for')
+                    self.loop_vars.add(words[1])
                     code.add_line(
-                        "for ctx[%r] in %s:" % (
+                        "for c_%s in %s:" % (
                             words[1],
                             self.expr_code(words[3])
                         )
@@ -126,7 +151,11 @@ class Templite(object):
             else:
                 # Literal content.  If it isn't empty, output it.
                 if tok:
-                    code.add_line("r(%r)" % tok)
+                    buffered.append("%r" % tok)
+        flush_output()
+
+        for var_name in self.all_vars - self.loop_vars:
+            vars_code.add_line("c_%s = ctx[%r]" % (var_name, var_name))
 
         if ops_stack:
             raise SyntaxError("Unmatched action tag: %r" % ops_stack[-1])
@@ -141,14 +170,16 @@ class Templite(object):
             pipes = expr.split("|")
             code = self.expr_code(pipes[0])
             for func in pipes[1:]:
-                code = "ctx[%r](%s)" % (func, code)
+                self.all_vars.add(func)
+                code = "c_%s(%s)" % (func, code)
         elif "." in expr:
             dots = expr.split(".")
             code = self.expr_code(dots[0])
             args = [repr(d) for d in dots[1:]]
             code = "dot(%s, %s)" % (code, ", ".join(args))
         else:
-            code = "ctx[%r]" % expr
+            self.all_vars.add(expr)
+            code = "c_%s" % expr
         return code
 
     def render(self, context=None):
@@ -161,7 +192,6 @@ class Templite(object):
         ctx = dict(self.context)
         if context:
             ctx.update(context)
-
         return self.render_function(ctx, self.do_dots)
 
     def do_dots(self, value, *dots):