Error recovery

.gitattributes

@@ -0,0 +1 @@
+*.dot diff=-astextplain

.vscode/launch.json

@@ -38,7 +38,7 @@
             "request": "launch",
             "mainClass": "org.rascalmpl.shell.RascalShell",
             "projectName": "rascal",
-            "cwd" : "${workspaceFolder}/../rascal-tutor",
+            "cwd": "${workspaceFolder}/../rascal-tutor",
             "vmArgs": "-Xss80m -Xmx2g -ea"
         },
         {

pom.xml

@@ -168,6 +168,7 @@
                             <goal>package</goal>
                         </goals>
                     </execution>
+		    <!--
                     <execution>
                         <id>default-cli</id>
                         <phase>compile</phase>
@@ -190,6 +191,7 @@
                             </ignores>
                         </configuration>
                         </execution>
+		    -->
                 </executions>
             </plugin>
             <plugin>

src/org/rascalmpl/interpreter/Evaluator.java

@@ -989,7 +989,7 @@
         IMap syntaxDefinition = curMod.getSyntaxDefinition();
         IMap grammar = (IMap) getParserGenerator().getGrammarFromModules(getMonitor(), curMod.getName(), syntaxDefinition).get("rules");
         IConstructor reifiedType = vf.reifiedType(dummy, grammar);
-        return vf.parsers(reifiedType, vf.bool(false), vf.bool(false), vf.bool(false), vf.set()); 
+        return vf.parsers(reifiedType, vf.bool(false), vf.bool(false), vf.bool(false), vf.bool(false), vf.set()); 
     }
 
     private Result<IValue> evalMore(String command, ISourceLocation location)

src/org/rascalmpl/library/Prelude.java

@@ -2377,20 +2377,24 @@
 
 	protected final TypeReifier tr;
 
+	public IFunction parser(IValue start,  IBool allowAmbiguity, IBool allowRecovery, IBool hasSideEffects, ISet filters) {
+	    return rascalValues.parser(start, allowAmbiguity, allowRecovery, hasSideEffects, values.bool(false), filters);
+	}
+
 	public IFunction parser(IValue start,  IBool allowAmbiguity, IBool hasSideEffects, ISet filters) {
-	    return rascalValues.parser(start, allowAmbiguity, hasSideEffects, values.bool(false), filters);
+	    return rascalValues.parser(start, allowAmbiguity, values.bool(false), hasSideEffects, values.bool(false), filters);
 	}
 
-	public IFunction firstAmbiguityFinder(IValue start, IBool hasSideEffects, ISet filters) {
-	    return rascalValues.parser(start, values.bool(true), hasSideEffects, values.bool(true), filters);
+	public IFunction firstAmbiguityFinder(IValue start, IBool allowRecovery, IBool hasSideEffects, ISet filters) {
+	    return rascalValues.parser(start, values.bool(true), allowRecovery, hasSideEffects, values.bool(true), filters);
 	}
 
-	public IFunction parsers(IValue start,  IBool allowAmbiguity, IBool hasSideEffects, ISet filters) {
-        return rascalValues.parsers(start, allowAmbiguity, hasSideEffects, values.bool(false), filters);
+	public IFunction parsers(IValue start,  IBool allowAmbiguity, IBool allowRecovery, IBool hasSideEffects, ISet filters) {
+        return rascalValues.parsers(start, allowAmbiguity, allowRecovery, hasSideEffects, values.bool(false), filters);
     }
 
-	public IFunction firstAmbiguityFinders(IValue start, IBool hasSideEffects, ISet filters) {
-        return rascalValues.parsers(start, values.bool(true), hasSideEffects, values.bool(true), filters);
+	public IFunction firstAmbiguityFinders(IValue start, IBool allowRecovery, IBool hasSideEffects, ISet filters) {
+        return rascalValues.parsers(start, values.bool(true), allowRecovery, hasSideEffects, values.bool(true), filters);
     }
 
 	public void storeParsers(IValue start, ISourceLocation saveLocation) {
@@ -2405,18 +2409,18 @@
 		}
 	}
 
-	public IFunction loadParsers(ISourceLocation savedLocation, IBool allowAmbiguity, IBool hasSideEffects, ISet filters) {
+	public IFunction loadParsers(ISourceLocation savedLocation, IBool allowAmbiguity, IBool allowRecovery, IBool hasSideEffects, ISet filters) {
 		try {
-			return rascalValues.loadParsers(savedLocation, allowAmbiguity, hasSideEffects, values.bool(false), filters);
+			return rascalValues.loadParsers(savedLocation, allowAmbiguity, allowRecovery, hasSideEffects, values.bool(false), filters);
 		}
 		catch (IOException | ClassNotFoundException e) {
 			throw RuntimeExceptionFactory.io(e.getMessage());
 		}
 	}
 
-	public IFunction loadParser(IValue grammar, ISourceLocation savedLocation, IBool allowAmbiguity, IBool hasSideEffects, ISet filters) {
+	public IFunction loadParser(IValue grammar, ISourceLocation savedLocation, IBool allowRecovery, IBool allowAmbiguity, IBool hasSideEffects, ISet filters) {
 		try {
-			return rascalValues.loadParser(grammar, savedLocation, allowAmbiguity, hasSideEffects, values.bool(false), filters);
+			return rascalValues.loadParser(grammar, savedLocation, allowAmbiguity, allowRecovery, hasSideEffects, values.bool(false), filters);
 		}
 		catch (IOException | ClassNotFoundException e) {
 			throw RuntimeExceptionFactory.io(e.getMessage());

src/org/rascalmpl/library/lang/c90/examples/hello-world.c

@@ -0,0 +1,19 @@
+
+int print(const char *text); 
+
+void printHello(char *name) {
+  print("Hello ");
+  print(name);
+  print("!");
+}
+
+int main(int argc, char *argv[]) {                                                        
+  char *name;
+  if (argc > 1) {
+    name = argv[1];
+  } else {
+    name = "World";
+  }
+
+  printHello(name);
+}

src/org/rascalmpl/library/lang/diff/unified/UnifiedDiff.rsc

@@ -3,6 +3,8 @@
 @contributor{Tijs van der Storm - [email protected] (CWI)}
 module lang::diff::unified::UnifiedDiff
 
+start syntax DiffFile = Diff;
+
 syntax Diff
   = Header old Header new Chunk* chunks
   ;

src/org/rascalmpl/library/lang/diff/unified/examples/example.diff

@@ -0,0 +1,39 @@
+--- a/src/org/rascalmpl/parser/uptr/UPTRNodeFactory.java
++++ b/src/org/rascalmpl/parser/uptr/UPTRNodeFactory.java
+@@ -1,6 +1,7 @@
+ package org.rascalmpl.parser.uptr;
+
+ import java.net.URI;
++import java.util.Arrays;
+ import java.util.IdentityHashMap;
+ import java.util.Map;
+
+@@ -21,7 +22,9 @@ import org.rascalmpl.values.parsetrees.ProductionAdapter;
+ import org.rascalmpl.values.parsetrees.TreeAdapter;
+
+ public class UPTRNodeFactory implements INodeConstructorFactory<ITree, ISourceLocation>{
+-	private final static RascalValueFactory VF = (RascalValueFactory) ValueFactoryFactory.getValueFactory();
++	private static final RascalValueFactory VF = (RascalValueFactory) ValueFactoryFactory.getValueFactory();
++	private static final IConstructor SKIPPED = VF.constructor(RascalValueFactory.Production_Skipped, VF.constructor(RascalValueFactory.Symbol_IterStar, VF.constructor(RascalValueFactory.Symbol_CharClass, VF.list(VF.constructor(RascalValueFactory.CharRange_Range, VF.integer(1), VF.integer(Character.MAX_CODE_POINT))))));
++
+ 	private boolean allowAmb;
+
+ 	public UPTRNodeFactory(boolean allowAmbiguity){
+@@ -141,7 +144,14 @@ public class UPTRNodeFactory implements INodeConstructorFactory<ITree, ISourceLo
+ 	}
+
+     @Override
+-    public ITree createRecoveryNode(int[] characters) {
+-       throw new UnsupportedOperationException(); 
+-    }
++    public ITree createSkippedNode(int[] characters) {
++		return createLiteralNode(characters, SKIPPED);
++	}
++
++	public ITree createErrorNode(ArrayList<ITree> children, Object production) {
++		IConstructor prod = (IConstructor) production;
++		IConstructor errorProd = VF.constructor(RascalValueFactory.Production_Error, prod.get(0), prod, VF.integer(children.size()-1));
++		return buildAppl(children, errorProd);
++	}
++
+ }

src/org/rascalmpl/library/lang/dot/examples/parser-state.dot

@@ -0,0 +1,65 @@
+digraph Parser {
+"Parser"["label"="Parser\nInput: \"void f(){if(1){}}\"\nLocation: 0 ('v')\nStep 5: Reducing terminals"];
+"todo-1"["label"="<0> 0", "shape"="record"];
+"-2"["label"="Epsilon: \n.0@0 ,matchable,end\n?\nin: 'lex(\"LAYOUT\") -> regular(\iter-star(lex(\"LAYOUT\")))'"];
+"7226"["label"="List: 7226\n.0@0 ,expandable,end\n7226\nin: 'LAYOUTLIST -> \iter-star(lex(\"LAYOUT\"))'"];
+"12860"["label"="NonTerminal: LAYOUTLIST\n.1@0 \nlayouts_LAYOUTLIST\nin: Tags Visibility Signature '=' Expression 'when' 12878 ';'"];
+"-1"["label"="NonTerminal: FunctionDeclaration\n.0@-1 \nFunctionDeclaration"];
+"12860" -> "-1";
+"7226" -> "12860";
+"-2" -> "7226";
+"todo-1":"0":sw -> "-2"["label"="Stack"];
+"46484886"["shape"="octagon", "label"="Epsilon"];
+"todo-1":"0":se -> "46484886"["label"="Node"];
+"todoLists":"1" -> "todo-1";
+"todoLists"["label"="<0> 0 | <1> 1 | <2> 2 | <3> 3 | <4> 4 | <5> 5 | <6> 6 | <7> 7 | <8> 8 | <9> 9 | <10> 10 | <11> 11 | <12> 12 | <13> 13 | <14> 14 | <15> 15", "shape"="record"];
+"Parser" -> "todoLists"["label"="todo lists"];
+"stacksToExpand"["label"="", "shape"="record"];
+"Parser" -> "stacksToExpand"["label"="stacks to expand"];
+"terminalsToReduce"["label"="<0> 0", "shape"="record", "color"="red"];
+"terminalsToReduce":"0":sw -> "-2"["label"="Stack"];
+"terminalsToReduce":"0":se -> "46484886"["label"="Node"];
+"Parser" -> "terminalsToReduce"["label"="terminals to reduce"];
+"nonTerminalsToReduce"["label"="", "shape"="record"];
+"Parser" -> "nonTerminalsToReduce"["label"="non-terminals to reduce"];
+"122"["label"="NonTerminal: Tag\n.0@0 ,end\nTag\nin: 'sort(\"Tag\") -> regular(\iter-star-seps(sort(\"Tag\"),[layouts(\"LAYOUTLIST\")]))'"];
+"124"["label"="SeparatedList: 124\n.0@0 ,expandable,end\n124\nin: 'default -> tags'"];
+"12858"["label"="NonTerminal: Tags\n.0@0 \nTags\nin: Tags Visibility Signature '=' Expression 'when' 12878 ';'"];
+"12858" -> "-1";
+"124" -> "12858";
+"122" -> "124";
+"unexpandableNodes":"0" -> "122";
+"13120"["label"="NonTerminal: Comment\n.0@0 ,end\nComment\nin: 'LAYOUT -> Comment'"];
+"7221"["label"="NonTerminal: LAYOUT\n.0@0 ,end\nLAYOUT\nin: 'lex(\"LAYOUT\") -> regular(\iter-star(lex(\"LAYOUT\")))'"];
+"7221" -> "7226";
+"13120" -> "7221";
+"unexpandableNodes":"1" -> "13120";
+"unexpandableNodes"["label"="<0> 0 | <1> 1", "shape"="record"];
+"12824"["label"="Char: \n.0@-1 ,matchable\n0\nin: 0 'sort(\"FunctionDeclaration\")' ':' 12828 0"];
+"unmatchableLeafNodes":"0" -> "12824";
+"128"["label"="Char: \n.0@-1 ,matchable\n0\nin: 0 'sort(\"Tags\")' ':' 132 0"];
+"unmatchableLeafNodes":"1" -> "128";
+"2043"["label"="Literal: \n.0@-1 ,matchable\n'@'\nin: '@' Name '=' Expression"];
+"unmatchableLeafNodes":"2" -> "2043";
+"2065"["label"="Char: \n.0@-1 ,matchable\n0\nin: 0 '\iter-star(sort(\"Tag\"))' ':' 2069 0"];
+"unmatchableLeafNodes":"3" -> "2065";
+"13122"["label"="Char: \n.0@-1 ,matchable,end\n9-13,32,133,160,5760,6158,8192-8202,8232-8233,8239,8287,12288\nin: 'LAYOUT -> [range(9,13),range(32,32),range(133,133),range(160,160),range(5760,5760),range(6158,6158),range(8192,8202),range(8232,8233),range(8239,8239),range(8287,8287),range(12288,12288)]'"];
+"unmatchableLeafNodes":"4" -> "13122";
+"13125"["label"="Char: \n.0@-1 ,matchable\n0\nin: 0 '\iter-star(sort(\"LAYOUT\"))' ':' 13129 0"];
+"unmatchableLeafNodes":"5" -> "13125";
+"7373"["label"="Literal: \n.0@-1 ,matchable\n'/*'\nin: '/*' 7379 '*/'"];
+"unmatchableLeafNodes":"6" -> "7373";
+"7382"["label"="Literal: \n.0@-1 ,matchable\n'//'\nin: '//' 7386"];
+"unmatchableLeafNodes":"7" -> "7382";
+"7389"["label"="Char: \n.0@-1 ,matchable\n0\nin: 0 'sort(\"Comment\")' ':' 7393 0"];
+"unmatchableLeafNodes":"8" -> "7389";
+"unmatchableLeafNodes"["label"="<0> 0 | <1> 1 | <2> 2 | <3> 3 | <4> 4 | <5> 5 | <6> 6 | <7> 7 | <8> 8", "shape"="record"];
+"unmatchableMidProductionNodes"["shape"="record", "label"=""];
+"filteredNodes"["label"="", "shape"="record"];
+"error"["label"="Errors"];
+"Parser" -> "error"["label"="error tracking"];
+"error" -> "unexpandableNodes"["label"="unexpandable"];
+"error" -> "unmatchableLeafNodes"["label"="unmatchable leafs"];
+"error" -> "unmatchableMidProductionNodes"["label"="unmatchable mid-prod"];
+"error" -> "filteredNodes"["label"="filtered"];
+}

src/org/rascalmpl/library/lang/dot/syntax/Dot.rsc

@@ -68,7 +68,7 @@ syntax NodeId
   | Id Port
   ;
 
-syntax Port = ":" Id Id?
+syntax Port = ":" Id (":" Id)?
 //          | ":" Id
 //          | ":" CompassPt
             ;

src/org/rascalmpl/library/lang/pico/examples/fac.pico

@@ -0,0 +1,18 @@
+begin declare input : natural,  
+              output : natural,      
+              repnr : natural,
+              rep : natural,
+              s1 : string,
+              s2 : string;
+      input := 14;
+      output := 1;
+      while input - 1 do 
+          rep := output;
+          repnr := input;
+          while repnr - 1 do
+             output := output + rep;
+             repnr := repnr - 1
+          od;
+          input := input - 1
+      od
+end

src/org/rascalmpl/library/lang/rascal/tests/concrete/recovery/BasicRecoveryTests.rsc

@@ -0,0 +1,47 @@
+/**
+ * Copyright (c) 2024, NWO-I Centrum Wiskunde & Informatica (CWI)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ **/
+
+module lang::rascal::tests::concrete::recovery::BasicRecoveryTests
+
+import ParseTree;
+
+layout Layout = [\ ]* !>> [\ ];
+
+syntax S = T;
+
+syntax T = ABC End;
+syntax ABC = 'a' 'b' 'c';
+syntax End = "$";
+
+private Tree parseS(str input, bool visualize=false)
+    = parser(#S, allowRecovery=true, allowAmbiguity=true)(input, |unknown:///?visualize=<"<visualize>">|);
+
+test bool basicOk() {
+    return !hasErrors(parseS("a b c $"));
+}
+
+test bool abx() {
+    Tree t = parseS("a b x $");
+    return getErrorText(findBestError(t)) == "x ";
+}
+
+test bool axc() {
+    Tree t = parseS("a x c $");
+    return getErrorText(findBestError(t)) == "x c";
+}
+
+test bool ax() {
+    Tree t = parseS("a x $");
+    return getErrorText(findBestError(t)) == "x ";
+}

src/org/rascalmpl/library/lang/rascal/tests/concrete/recovery/ErrorRecoveryBenchmark.rsc

@@ -0,0 +1,58 @@
+module lang::rascal::tests::concrete::recovery::ErrorRecoveryBenchmark
+
+import lang::rascal::tests::concrete::recovery::RecoveryTestSupport;
+
+import IO;
+import util::Benchmark;
+import String;
+import List;
+
+void runTestC() { testRecoveryC(); }
+void runTestDiff() { testRecoveryDiff(); }
+void runTestDot() { testRecoveryDot(); }
+void runTestJava() { testRecoveryJava(); }
+void runTestJson() { testRecoveryJson(); }
+void runTestPico() { testRecoveryPico(); }
+void runTestRascal() { testRecoveryRascal(); }
+
+FileStats testRecoveryC() = testErrorRecovery(|std:///lang/c90/syntax/C.rsc|, "TranslationUnit", |std:///lang/c90/examples/hello-world.c|);
+FileStats testRecoveryDiff() = testErrorRecovery(|std:///lang/diff/unified/UnifiedDiff.rsc|, "DiffFile", |std:///lang/diff/unified/examples/example.diff|);
+FileStats testRecoveryDot() = testErrorRecovery(|std:///lang/dot/syntax/Dot.rsc|, "DOT", |std:///lang/dot/examples/parser-state.dot|);
+FileStats testRecoveryJava() = testErrorRecovery(|std:///lang/java/syntax/Java15.rsc|, "CompilationUnit", zippedFile("m3/snakes-and-ladders-project-source.zip", "src/snakes/LastSquare.java"));
+FileStats testRecoveryJson() = testErrorRecovery(|std:///lang/json/syntax/JSON.rsc|, "JSONText", |std:///lang/json/examples/ex01.json|);
+FileStats testRecoveryPico() = testErrorRecovery(|std:///lang/pico/syntax/Main.rsc|, "Program", |std:///lang/pico/examples/fac.pico|);
+FileStats testRecoveryRascal() = testErrorRecovery(|std:///lang/rascal/syntax/Rascal.rsc|, "Module", |std:///lang/rascal/vis/ImportGraph.rsc|);
+
+void runLanguageTests() {
+    testRecoveryC();
+    testRecoveryDiff();
+    testRecoveryDot();
+    testRecoveryJava();
+    testRecoveryJson();
+    testRecoveryPico();
+    testRecoveryRascal();
+}
+
+void runRascalBatchTest(int maxFiles=1000, int maxFileSize=4000) {
+    int startTime = realTime();
+    TestStats stats = batchRecoveryTest(|std:///lang/rascal/syntax/Rascal.rsc|, "Module", |std:///|, ".rsc", maxFiles, maxFileSize);
+    int duration = realTime() - startTime;
+    println();
+    println("========================im========================================");
+    println("Rascal batch test done in <duration/1000> seconds, total result:");
+    printStats(stats);
+}
+
+int main(list[str] args) {
+    int maxFiles = 1000;
+    int maxFileSize = 4000;
+    if (size(args) == 2) {
+        maxFiles = toInt(args[0]);
+        maxFileSize = toInt(args[1]);
+    } else if (size(args) != 0) {
+        println("Usage: ErrorRecoveryBenchmark <max-files> <max-file-size>");
+    }
+
+    runRascalBatchTest(maxFiles=maxFiles, maxFileSize=maxFileSize);
+    return 0;
+}