Add a ParseDepends() function to read up mkdep-style files.

5 files changed, 111 insertions, 0 deletions

diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index df2a93a..9fa7b34 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -792,6 +792,32 @@ class Base:
         command = self.subst(command)
         return function(self, os.popen(command).read())
 
+    def ParseDepends(self, filename, must_exist=None):
+        """
+        Parse a mkdep-style file for explicit dependencies.  This is
+        completely abusable, and should be unnecessary in the "normal"
+        case of proper SCons configuration, but it may help make
+        the transition from a Make hierarchy easier for some people
+        to swallow.  It can also be genuinely useful when using a tool
+        that can write a .d file, but for which writing a scanner would
+        be too complicated.
+        """
+        try:
+            fp = open(filename, 'r')
+        except IOError:
+            if must_exist:
+                raise
+            return
+        for line in SCons.Util.LogicalLines(fp).readlines():
+            if line[0] == '#':
+                continue
+            try:
+                target, depends = string.split(line, ':', 1)
+            except:
+                pass
+            else:
+                self.Depends(string.split(target), string.split(depends))
+
     def Platform(self, platform):
         platform = self.subst(platform)
         return SCons.Platform.Platform(platform)(self)
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index 7023fea..aa38965 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -1353,6 +1353,38 @@ class EnvironmentTestCase(unittest.TestCase):
         finally:
             os.popen = orig_popen
 
+    def test_ParseDepends(self):
+        """Test the ParseDepends() method"""
+        env = Environment()
+
+        test = TestCmd.TestCmd(workdir = '')
+
+        test.write('mkdep', """
+f1: foo
+f2 f3: bar
+f4: abc def
+#file: dependency
+f5: \
+   ghi \
+   jkl \
+   mno \
+""")
+
+        tlist = []
+        dlist = []
+        def my_depends(target, dependency, tlist=tlist, dlist=dlist):
+            tlist.extend(target)
+            dlist.extend(dependency)
+
+        env.Depends = my_depends
+
+        env.ParseDepends(test.workpath('mkdep'))
+
+        t = map(str, tlist)
+        d = map(str, dlist)
+        assert t == ['f1', 'f2', 'f3', 'f4', 'f5'], t
+        assert d == ['foo', 'bar', 'abc', 'def', 'ghi', 'jkl', 'mno'], d
+
     def test_Platform(self):
         """Test the Platform() method"""
         env = Environment(WIN32='win32', NONE='no-such-platform')
diff --git a/src/engine/SCons/Script/SConscript.py b/src/engine/SCons/Script/SConscript.py
index fab0d82..88d3268 100644
--- a/src/engine/SCons/Script/SConscript.py
+++ b/src/engine/SCons/Script/SConscript.py
@@ -594,6 +594,7 @@ GlobalDefaultEnvironmentFunctions = [
     'InstallAs',
     'Literal',
     'Local',
+    'ParseDepends',
     'Precious',
     'Repository',
     'SConsignFile',
diff --git a/src/engine/SCons/Util.py b/src/engine/SCons/Util.py
index df2f604..afcaf11 100644
--- a/src/engine/SCons/Util.py
+++ b/src/engine/SCons/Util.py
@@ -1520,3 +1520,32 @@ def unique(s):
         if x not in u:
             u.append(x)
     return u
+
+# Much of the logic here was originally based on recipe 4.9 from the
+# Python CookBook, but we had to dumb it way down for Python 1.5.2.
+class LogicalLines:
+
+    def __init__(self, fileobj):
+        self.fileobj = fileobj
+
+    def readline(self):
+        result = []
+        while 1:
+            line = self.fileobj.readline()
+            if not line:
+                break
+            if line[-2:] == '\\\n':
+                result.append(line[:-2])
+            else:
+                result.append(line)
+                break
+        return string.join(result, '')
+
+    def readlines(self):
+        result = []
+        while 1:
+            line = self.readline()
+            if not line:
+                break
+            result.append(line)
+        return result
diff --git a/src/engine/SCons/UtilTests.py b/src/engine/SCons/UtilTests.py
index 2b5fdef..054d0b2 100644
--- a/src/engine/SCons/UtilTests.py
+++ b/src/engine/SCons/UtilTests.py
@@ -1552,6 +1552,29 @@ class UtilTestCase(unittest.TestCase):
         assert containsOnly('.83', '0123456789.')
         assert not containsOnly('43221', '123')
 
+    def test_LogicalLines(self):
+        """Test the LogicalLines class"""
+        import StringIO
+
+        fobj = StringIO.StringIO(r"""
+foo \
+bar \
+baz
+foo
+bling \
+bling \ bling
+bling
+""")
+
+        lines = LogicalLines(fobj).readlines()
+        assert lines == [
+            '\n',
+            'foo bar baz\n',
+            'foo\n',
+            'bling bling \\ bling\n',
+            'bling\n',
+        ], lines
+
 if __name__ == "__main__":
     suite = unittest.makeSuite(UtilTestCase, 'test_')
     if not unittest.TextTestRunner().run(suite).wasSuccessful():