Merge branch '__rultor'

objectionary · Mar 19, 2024 · 97054f3 · 97054f3 · 0pdd · Mar 19, 2024
2 parents 446d62f + b112122
commit 97054f3
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Showing 3 changed files with 18 additions and 1 deletion.
diff --git a/eo-parser/src/main/antlr4/org/eolang/parser/Phi.g4 b/eo-parser/src/main/antlr4/org/eolang/parser/Phi.g4
@@ -58,7 +58,7 @@ emptyBinding
     ;
 
 deltaBidning
-    : DELTA DASHED_ARROW BYTES
+    : DELTA DASHED_ARROW (BYTES | EMPTY)
     ;
 
 lambdaBidning

diff --git a/eo-parser/src/main/java/org/eolang/parser/XePhiListener.java b/eo-parser/src/main/java/org/eolang/parser/XePhiListener.java
@@ -313,6 +313,13 @@ public void exitEmptyBinding(final PhiParser.EmptyBindingContext ctx) {
 
     @Override
     public void enterDeltaBidning(final PhiParser.DeltaBidningContext ctx) {
+        if (ctx.EMPTY() != null) {
+            throw new ParsingException(
+                "It's impossible to represent Δ ⤍ ∅ binding in EO",
+                new IllegalStateException(),
+                ctx.getStart().getLine()
+            );
+        }
         this.objects()
             .start()
             .prop("data", "bytes")

diff --git a/eo-parser/src/test/java/org/eolang/parser/PhiSyntaxTest.java b/eo-parser/src/test/java/org/eolang/parser/PhiSyntaxTest.java
@@ -26,6 +26,7 @@
 import com.jcabi.matchers.XhtmlMatchers;
 import java.io.IOException;
 import org.hamcrest.MatcherAssert;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.xembly.Directives;
 
@@ -48,6 +49,15 @@ void addsError() throws IOException {
         );
     }
 
+    @Test
+    void catchesDeltaToNothingBinding() throws IOException {
+        Assertions.assertThrows(
+            ParsingException.class,
+            new PhiSyntax("{ ⟦ x ↦ ⟦ Δ ⤍ ∅ ⟧ ⟧ }")::parsed,
+            "Impossible binding with Δ should be caught"
+        );
+    }
+
     @Test
     void addsExtra() throws IOException {
         MatcherAssert.assertThat(