gen_ir: Move SimpleLoader to jinjautil file

Also improve the comment a bit

Makefile

@@ -114,7 +114,7 @@ IR_SPEC_GENERATED_INCLUDES := \
 	$(gendir)/ir/ir/gen_irdump.c.inl  \
 	$(gendir)/ir/ir/gen_irnode.h
 IR_SPEC_GENERATOR := $(srcdir)/scripts/gen_ir.py
-IR_SPEC_GENERATOR_DEPS := $(IR_SPEC_GENERATOR) $(srcdir)/scripts/spec_util.py $(srcdir)/scripts/filters.py
+IR_SPEC_GENERATOR_DEPS := $(IR_SPEC_GENERATOR) $(srcdir)/scripts/jinjautil.py $(srcdir)/scripts/spec_util.py $(srcdir)/scripts/filters.py
 IR_SPEC := $(srcdir)/scripts/ir_spec.py
 libfirm_BUILDDIRS += $(gendir)/include/libfirm
 

configure

@@ -135,8 +135,8 @@ def specgen(out, template=None):
 		template = "$srcdir/scripts/templates/" + basename(out)
 	generator = "$srcdir/scripts/gen_ir.py"
 	specfile = "$srcdir/scripts/ir_spec.py"
-	deps = [template, specfile, generator, "$srcdir/scripts/spec_util.py",
-	        "$srcdir/scripts/filters.py"]
+	deps = [template, specfile, generator, "$srcdir/scripts/jinjautil.py",
+			"$srcdir/scripts/spec_util.py", "$srcdir/scripts/filters.py"]
 	return build("GEN_IR", out, deps, specfile=specfile,
 	             template=template, generatortool=generator)
 

scripts/gen_ir.py

@@ -5,7 +5,8 @@
 import sys
 import argparse
 from datetime import datetime
-from jinja2 import Environment, Template, BaseLoader
+from jinja2 import Environment, Template
+import jinjautil
 from spec_util import is_dynamic_pinned, isAbstract, setdefault, load_spec, Attribute
 from filters import arguments, filtjoin, has, hasnot
 
@@ -232,30 +233,7 @@ def parse_tagfile(filename):
 	except:
 		tags = None
 
-# simple FileSystemLoader variant. Compared to the default loader in jinja
-# it does not perform searchpath magic and does not reject paths containig ".."
-# for security.
-# Note that we want to use a loader instead of simply env.from_string because
-# we want to see the filename in error messages from jinja
-class SimpleLoader(BaseLoader):
-	def __init__(self):
-		super(SimpleLoader, self).__init__()
-		self.includedirs = [""]
-	def get_source(self, environment, name):
-		for dir in self.includedirs:
-			try:
-				path = name if dir == "" else "%s/%s" % (dir, name)
-				contents = open(path).read()
-			except:
-				continue
-			def uptodate():
-				return False
-			return contents, name, uptodate
-		raise Exception("Could not open '%s'" % name)
-	def list_template(self):
-		return []
-
-loader = SimpleLoader()
+loader = jinjautil.SimpleLoader()
 env = Environment(loader=loader, keep_trailing_newline=True)
 env.filters['a_an']               = a_an
 env.filters['args']               = args

scripts/jinjautil.py

+# This file is part of libFirm.
+# Copyright (C) 2015 Matthias Braun
+from jinja2 import BaseLoader
+
+# Simple FileSystemLoader variant. Compared to the default loader in jinja
+# it does not perform searchpath magic and does not reject paths containig ".."
+# (the jinja one does that for security reasons).
+# Note that simply using env.from_string is a not a good alternative as then we
+# don't see filename and proper line in error messages from jinja
+class SimpleLoader(BaseLoader):
+	def __init__(self):
+		super(SimpleLoader, self).__init__()
+		self.includedirs = [""]
+	def get_source(self, environment, name):
+		for dir in self.includedirs:
+			try:
+				path = name if dir == "" else "%s/%s" % (dir, name)
+				contents = open(path).read()
+			except:
+				continue
+			def uptodate():
+				return False
+			return contents, name, uptodate
+		raise Exception("Could not open '%s'" % name)
+	def list_template(self):
+		return []