coloring: Only generate strictly positive IDs

This will allow to reserve negative IDs (including 0) for special purposes.

Signed-off-by: Jean-Christophe Beaupré <jcbrinfo@users.noreply.github.com>

diff --git a/src/compiler/coloring.nit b/src/compiler/coloring.nit
index 9b3748b..80f29ec 100644 (file)
--- a/src/compiler/coloring.nit
+++ b/src/compiler/coloring.nit
@@ -178,6 +178,9 @@ class POSetColorer[E: Object]
        var is_colored = false
 
        # Resulting ids
+       #
+       # All ids are strictly positive (`>= 1`).
+       #
        # REQUIRE: is_colored
        fun ids: Map[E, Int] do
                assert is_colored
@@ -223,7 +226,7 @@ class POSetColorer[E: Object]
                ids_cache.clear
                var elements = new HashSet[E].from(poset_cache.to_a)
                for e in poset_cache.linearize(elements) do
-                       ids_cache[e] = ids_cache.length
+                       ids_cache[e] = ids_cache.length + 1
                end
        end
 

diff --git a/src/compiler/test_coloring.nit b/src/compiler/test_coloring.nit
new file mode 100644 (file)
index 0000000..867afcf
--- /dev/null
+++ b/src/compiler/test_coloring.nit
@@ -0,0 +1,32 @@
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+module test_coloring is test_suite
+
+import test_suite
+import coloring
+
+class TestPOSetColorer
+       super TestSuite
+
+       fun test_ids_strictly_positive do
+               var poset = new POSet[String]
+               poset.add_node "A"
+
+               var colorer = new POSetColorer[String]
+               colorer.colorize(poset)
+
+               assert colorer.ids["A"] > 0
+       end
+end