Check that sub-functions in replacement patterns are defined

core/src/main/java/it/cavallium/warppi/math/rules/dsl/PatternRule.java

@@ -53,6 +53,14 @@ public class PatternRule implements Rule {
 		return ruleType;
 	}
 
+	Pattern getTarget() {
+		return target;
+	}
+
+	List<Pattern> getReplacements() {
+		return replacements;
+	}
+
 	@Override
 	public ObjectArrayList<Function> execute(final Function func) throws Error, InterruptedException {
 		return target.match(func)

core/src/main/java/it/cavallium/warppi/math/rules/dsl/RulesDsl.java

@@ -3,9 +3,11 @@ package it.cavallium.warppi.math.rules.dsl;
 import it.cavallium.warppi.math.rules.Rule;
 import it.cavallium.warppi.math.rules.dsl.frontend.Lexer;
 import it.cavallium.warppi.math.rules.dsl.frontend.Parser;
+import it.cavallium.warppi.math.rules.dsl.patterns.SubFunctionPattern;
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 public class RulesDsl {
 	private RulesDsl() {}
@@ -13,6 +15,28 @@ public class RulesDsl {
 	public static List<Rule> makeRules(final String source) {
 		final Lexer lexer = new Lexer(source);
 		final Parser parser = new Parser(lexer.lex());
-		return Collections.unmodifiableList(parser.parse());
+		final List<PatternRule> rules = parser.parse();
+
+		for (final PatternRule rule : rules) {
+			checkSubFunctionsDefined(rule);
+		}
+
+		return Collections.unmodifiableList(rules);
+	}
+
+	/**
+	 * Verifies that all sub-functions in the replacement patterns of a <code>PatternRule</code>
+	 * are defined (captured) in the target pattern.
+	 *
+	 * @param rule The rule to check.
+	 * @throws RuntimeException if any replacement pattern uses undefined sub-functions.
+	 */
+	private static void checkSubFunctionsDefined(final PatternRule rule) {
+		final Set<SubFunctionPattern> defined = rule.getTarget().getSubFunctions();
+		for (final Pattern replacement : rule.getReplacements()) {
+			if (!defined.containsAll(replacement.getSubFunctions())) {
+				throw new RuntimeException("Undefined sub-function(s) in replacements for " + rule.getRuleName());
+			}
+		}
 	}
 }

core/src/test/java/it/cavallium/warppi/math/rules/dsl/RulesDslTest.java

@@ -61,4 +61,9 @@ public class RulesDslTest {
 	public void parserError() {
 		RulesDsl.makeRules("existence test: x + y ->");
 	}
+
+	@Test(expected = RuntimeException.class)
+	public void undefinedSubFunction() {
+		RulesDsl.makeRules("expansion test: x -> x + y");
+	}
 }