Sort the dangling lines when creating a tie line to ensure reproducib…

…ility (#2874) Signed-off-by: Olivier Perrin <olivier.perrin@rte-france.com>
powsybl · Jan 26, 2024 · 251d866 · 251d866
1 parent b44532e
commit 251d866
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diff --git a/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java b/iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NetworkImpl.java
@@ -1068,6 +1068,11 @@ private void pairDanglingLines(List<DanglingLinePair> danglingLinePairs, Danglin
                 ((DanglingLineImpl) dl2).replaceId(l.dl2Id + "_2");
                 l.dl1Id = dl1.getId();
                 l.dl2Id = dl2.getId();
+            } else if (l.dl1Id.compareTo(l.dl2Id) > 0) {
+                // Invert the ids to always have them in lexicographical order (to ensure reproducibility)
+                var tmp = l.dl1Id;
+                l.dl1Id = l.dl2Id;
+                l.dl2Id = tmp;
             }
         }
     }

diff --git a/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractMergeNetworkTest.java b/iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractMergeNetworkTest.java
@@ -91,6 +91,8 @@ public void testMergeAndDetach() {
         assertNotNull(tieLine);
         assertEquals("dl1_name + dl2_name", tieLine.getOptionalName().orElse(null));
         assertEquals("dl1_name + dl2_name", tieLine.getNameOrId());
+        assertEquals("dl1", tieLine.getDanglingLine1().getId());
+        assertEquals("dl2", tieLine.getDanglingLine2().getId());
         assertEquals(0.0, tieLine.getDanglingLine1().getP0());
         assertEquals(0.0, tieLine.getDanglingLine1().getQ0());
         assertEquals(0.0, tieLine.getDanglingLine2().getP0());
@@ -624,6 +626,18 @@ public void mergeThenCloneVariantBug() {
         assertEquals(0, ld2.getP0(), 0);
     }
 
+    @Test
+    public void invertDanglingLinesWhenCreatingATieLine() {
+        addCommonSubstationsAndVoltageLevels();
+        addCommonDanglingLines("dl2", "code", "dl1", "code");
+        Network merge = Network.merge(n1, n2);
+        assertEquals(1, merge.getTieLineCount());
+        TieLine tieLine = merge.getTieLine("dl1 + dl2");
+        assertNotNull(tieLine);
+        assertEquals("dl1", tieLine.getDanglingLine1().getId());
+        assertEquals("dl2", tieLine.getDanglingLine2().getId());
+    }
+
     @Test
     public void dontCreateATieLineWithAlreadyMergedDanglingLinesInMergedNetwork() {
         // The code is not the same if the dangling line with the duplicate pairing key is in the current network