Fix spurious rebuilds/reinstalls of header files and circular dependencies with generated header files by allowing Scanners to be associated explicitly with Builders, not just through Scanner file suffix lists.

5 files changed, 117 insertions, 0 deletions

diff --git a/src/engine/SCons/Scanner/CTests.py b/src/engine/SCons/Scanner/CTests.py
index f63060a..693ec18 100644
--- a/src/engine/SCons/Scanner/CTests.py
+++ b/src/engine/SCons/Scanner/CTests.py
@@ -193,6 +193,9 @@ class DummyEnvironment(UserDict.UserDict):
             path = [path]
         return map(self.subst, path)
 
+    def get_calculator(self):
+        return None
+
 if os.path.normcase('foo') == os.path.normcase('FOO'):
     my_normpath = os.path.normcase
 else:
diff --git a/src/engine/SCons/Scanner/FortranTests.py b/src/engine/SCons/Scanner/FortranTests.py
index e69f99e..766f0ee 100644
--- a/src/engine/SCons/Scanner/FortranTests.py
+++ b/src/engine/SCons/Scanner/FortranTests.py
@@ -168,6 +168,9 @@ class DummyEnvironment:
             path = [path]
         return map(self.subst, path)
 
+    def get_calculator(self):
+        return None
+
 def deps_match(self, deps, headers):
     scanned = map(os.path.normpath, map(str, deps))
     expect = map(os.path.normpath, headers)
diff --git a/src/engine/SCons/Scanner/IDLTests.py b/src/engine/SCons/Scanner/IDLTests.py
index c20dedc..876f492 100644
--- a/src/engine/SCons/Scanner/IDLTests.py
+++ b/src/engine/SCons/Scanner/IDLTests.py
@@ -218,6 +218,9 @@ class DummyEnvironment:
     def __delitem__(self,key):
         del self.Dictionary()[key]
 
+    def get_calculator(self):
+        return None
+
 global my_normpath
 my_normpath = os.path.normpath
 
diff --git a/src/engine/SCons/Scanner/ScannerTests.py b/src/engine/SCons/Scanner/ScannerTests.py
index 4e662a2..a0c6f01 100644
--- a/src/engine/SCons/Scanner/ScannerTests.py
+++ b/src/engine/SCons/Scanner/ScannerTests.py
@@ -65,6 +65,17 @@ class FindPathDirsTestCase(unittest.TestCase):
 
 class ScannerTestCase(unittest.TestCase):
 
+    def test_creation(self):
+        """Test creation of Scanner objects through the Scanner() function"""
+        def func(self):
+            pass
+        s = SCons.Scanner.Scanner(func)
+        assert isinstance(s, SCons.Scanner.Base), s
+        s = SCons.Scanner.Scanner({})
+        assert isinstance(s, SCons.Scanner.Selector), s
+
+class BaseTestCase(unittest.TestCase):
+
     def func(self, filename, env, target, *args):
         self.filename = filename
         self.env = env
@@ -192,6 +203,66 @@ class ScannerTestCase(unittest.TestCase):
         self.failUnless(sk == ['.3', '.4'],
                         "sk was %s, not ['.3', '.4']")
 
+    def test_select(self):
+        """Test the Scanner.Base select() method"""
+        scanner = SCons.Scanner.Base(function = self.func)
+        s = scanner.select('.x')
+        assert s is scanner, s
+
+class SelectorTestCase(unittest.TestCase):
+    class skey:
+        def __init__(self, key):
+            self.key = key
+        def scanner_key(self):
+            return self.key
+
+    def test___init__(self):
+        """Test creation of Scanner.Selector object"""
+        s = SCons.Scanner.Selector({})
+        assert isinstance(s, SCons.Scanner.Selector), s
+        assert s.dict == {}, s.dict
+
+    def test___call__(self):
+        """Test calling Scanner.Selector objects"""
+        called = []
+        def s1func(node, env, path, called=called):
+            called.append('s1func')
+            called.append(node)
+            return []
+        def s2func(node, env, path, called=called):
+            called.append('s2func')
+            called.append(node)
+            return []
+        s1 = SCons.Scanner.Base(s1func)
+        s2 = SCons.Scanner.Base(s2func)
+        selector = SCons.Scanner.Selector({'.x' : s1, '.y' : s2})
+        nx = self.skey('.x')
+        selector(nx, None, [])
+        assert called == ['s1func', nx], called
+        del called[:]
+        ny = self.skey('.y')
+        selector(ny, None, [])
+        assert called == ['s2func', ny], called
+
+    def test_select(self):
+        """Test the Scanner.Selector select() method"""
+        selector = SCons.Scanner.Selector({'.x' : 1, '.y' : 2})
+        s = selector.select(self.skey('.x'))
+        assert s == 1, s
+        s = selector.select(self.skey('.y'))
+        assert s == 2, s
+        s = selector.select(self.skey('.z'))
+        assert s is None, s
+
+    def test_add_scanner(self):
+        """Test the Scanner.Selector add_scanner() method"""
+        selector = SCons.Scanner.Selector({'.x' : 1, '.y' : 2})
+        s = selector.select(self.skey('.z'))
+        assert s is None, s
+        selector.add_scanner('.z', 3)
+        s = selector.select(self.skey('.z'))
+        assert s == 3, s
+
 class CurrentTestCase(unittest.TestCase):
     def test_class(self):
         """Test the Scanner.Current class"""
@@ -355,6 +426,8 @@ def suite():
     tclasses = [
                  FindPathDirsTestCase,
                  ScannerTestCase,
+                 BaseTestCase,
+                 SelectorTestCase,
                  CurrentTestCase,
                  ClassicTestCase,
                  ClassicCPPTestCase,
diff --git a/src/engine/SCons/Scanner/__init__.py b/src/engine/SCons/Scanner/__init__.py
index 8f6c9e6..8432638 100644
--- a/src/engine/SCons/Scanner/__init__.py
+++ b/src/engine/SCons/Scanner/__init__.py
@@ -43,6 +43,15 @@ class _Null:
 # used as an actual argument value.
 _null = _Null
 
+def Scanner(function, *args, **kw):
+    """Public interface factory function for creating different types
+    of Scanners based on the different types of "functions" that may
+    be supplied."""
+    if SCons.Util.is_Dict(function):
+        return apply(Selector, (function,) + args, kw)
+    else:
+        return apply(Base, (function,) + args, kw)
+
 class FindPathDirs:
     """A class to bind a specific *PATH variable name and the fs object
     to a function that will return all of the *path directories."""
@@ -190,6 +199,31 @@ class Base:
             return env.subst_list(self.skeys)[0]
         return self.skeys
 
+    def select(self, node):
+        return self
+
+
+class Selector(Base):
+    """
+    A class for selecting a more specific scanner based on the
+    scanner_key() (suffix) for a specific Node.
+    """
+    def __init__(self, dict, *args, **kw):
+        Base.__init__(self, (None,)+args, kw)
+        self.dict = dict
+
+    def __call__(self, node, env, path = ()):
+        return self.select(node)(node, env, path)
+
+    def select(self, node):
+        try:
+            return self.dict[node.scanner_key()]
+        except KeyError:
+            return None
+
+    def add_scanner(self, skey, scanner):
+        self.dict[skey] = scanner
+
 
 class Current(Base):
     """
@@ -200,6 +234,7 @@ class Current(Base):
 
     def __init__(self, *args, **kw):
         def current_check(node, env):
+            calc = env.get_calculator()
             c = not node.has_builder() or node.current(env.get_calculator())
             return c
         kw['scan_check'] = current_check