From: adam <adam@megacz.com>
Date: Sat, 29 Jul 2006 07:26:20 +0000 (-0400)
Subject: vast improvement in error reporting
X-Git-Tag: tag_for_25-Mar~91
X-Git-Url: http://git.megacz.com/?p=sbp.git;a=commitdiff_plain;h=62be1c1ae2ac13086b508e34eeffdb7e536d5b61

vast improvement in error reporting

darcs-hash:20060729072620-5007d-fcd503f30c8f029b2a9502dd42cafe3db8d09b0d.gz
---

diff --git a/src/edu/berkeley/sbp/GSS.java b/src/edu/berkeley/sbp/GSS.java
index b36b293..5255a21 100644
--- a/src/edu/berkeley/sbp/GSS.java
+++ b/src/edu/berkeley/sbp/GSS.java
@@ -94,9 +94,13 @@ class GSS {
         public boolean isDone() throws ParseFailed {
             if (token != null) return false;
             if (token==null && finalResult==null)
-                throw new ParseFailed(ParseFailed.error(("unexpected end of file\n"),
-                                                        token, hash.values()),
-                                      getLocation().createRegion(getLocation()), input);
+                ParseFailed.error("unexpected end of file",
+                                  getLocation(),
+                                  token,
+                                  hash.values(),
+                                  getLocation().createRegion(getLocation()),
+                                  input,
+                                  GSS.this);
             return true;
         }
 
@@ -253,14 +257,22 @@ class GSS {
             }
 
             if (!good && token!=null)
-                throw new ParseFailed(ParseFailed.error(("unexpected character ")+" \'"+
-                                                        ANSI.purple(StringUtil.escapify(token+"", "\\\'\r\n"))+
-                                                        "\' encountered at "+
-                                                        ANSI.green(next.getRegion())+"\n", token, hash.values()),
-                                        next.getRegion(), input);
+                ParseFailed.error("unexpected character",
+                                  getLocation(),
+                                  token,
+                                  hash.values(),
+                                  getRegion(),
+                                  input,
+                                  GSS.this);
+
             if (token==null && finalResult==null)
-                throw new ParseFailed(ParseFailed.error(("unexpected end of file at "+getLocation()+"\n"), token, hash.values()),
-                                      getLocation().createRegion(getLocation()), input);
+                ParseFailed.error("unexpected end of file",
+                                  getLocation(),
+                                  token,
+                                  hash.values(),
+                                  getLocation().createRegion(getLocation()),
+                                  input,
+                                  GSS.this);
         }
 
 
diff --git a/src/edu/berkeley/sbp/ParseFailed.java b/src/edu/berkeley/sbp/ParseFailed.java
index d5474ae..547ea95 100644
--- a/src/edu/berkeley/sbp/ParseFailed.java
+++ b/src/edu/berkeley/sbp/ParseFailed.java
@@ -16,62 +16,110 @@ public class ParseFailed extends Exception {
     private final Input.Region region;
     private final Input input;
     private final String message;
-    ParseFailed() { this("", null, null); }
-    ParseFailed(String message, Input.Region region, Input input) {
+    private final GSS gss;
+    ParseFailed() { this("", null, null, null); }
+    ParseFailed(String message, Input.Region region, Input input, GSS gss) {
         this.region = region;
         this.location = region.getStart();
         this.message = message;
         this.input = input;
+        this.gss = gss;
     }
     public Input.Location getLocation() { return location; }
     private Input.Region getRegion() { return region; }
     public String toString() {
-        Input.Location before = getRegion().getStart();
-        for(int i=0; i<10; i++) before = before.prev() == null ? before : before.prev();
-        Input.Location after = getRegion().getEnd();
-        for(int i=0; i<10; i++) after = after.next() == null ? after : after.next();
         StringBuilder ret = new StringBuilder();
         ret.append(message);
         ret.append('\n');
-        ret.append("      at: ");
-        ret.append(getRegion()+"");
-        if (input != null) {
-            ret.append('\n');
-            ret.append("    text: ");
-            String first = input.showRegion(before.createRegion(getRegion().getStart()));
-            ret.append(first);
-            String second = input.showRegion(getRegion());
-            ret.append(ANSI.red(second));
-            ret.append(input.showRegion(getRegion().getEnd().createRegion(after)));
-            ret.append('\n');
-            ret.append("          ");
-            for(int i=0; i<first.length(); i++) ret.append(' ');
-            for(int i=0; i<second.length(); i++) ret.append(ANSI.red("^"));
-        }
         return ret.toString();
     }
 
+    private static boolean important(Position p) {
+        if (p.isLast()) return false;
+        if (p.element() == null) return false;
+        if (!(p.element() instanceof Union)) return false;
+        Union u = (Union)p.element();
+        if (u.synthetic) return false;
+        if (u.name==null) return false;
+        if (u.name.length() == 0) return false;
+        char c = u.name.charAt(0);
+        return (c >= 'A' && c <= 'Z');
+    }
+
+    static <Tok> void barf(HashMap<Element,Input.Location> sb, GSS.Phase<Tok>.Node n, int indent, boolean skip, int count, Input.Location loc) {
+        if (count <= 0) {
+            barf(sb, n, indent, skip, loc);
+        } else {
+            for(GSS.Phase<Tok>.Node nn : n.parents())
+                barf(sb, nn, indent, skip, count-1, nn.phase().getPrevLocation());
+        }
+    }
+    static <Tok> void barf(HashMap<Element,Input.Location> sb, GSS.Phase<Tok>.Node n, int indent, boolean skip, Input.Location loc) {
+        if (touched.contains(n)) return;
+        touched.add(n);
+        String s = "";
+        for(int i=0; i< indent; i++) s += " ";
+        GSS.Phase<Tok>.Node parent = n;
+        boolean done = false;
+        boolean alldone = false;
+        boolean go = false;
+        boolean force = false;
+        for(Position p : parent.state) {
+            if (skip) p = p.next();
+            int raise = 0;
+            done = false;
+            while(p != null) {
+                if (p.isLast()) break;
+                if (important(p)) {
+                    Input.Location l = sb.get(p.element());
+                    if (l == null || l.compareTo(loc) < 0)
+                        sb.put(p.element(), loc);
+                    done = true;
+                    alldone = true;
+                }
+                /*
+               else if (p.pos-raise > 0)
+                    barf(sb, n, indent, false, 1);
+                */
+                if (!new Walk.Cache().possiblyEpsilon(p.element()))
+                    break;
+                p = p.next();
+                raise++;
+                if (p.isLast()) {
+                    if (!done) barf(sb, n, indent, true, 1, loc);
+                    break;
+                }
+            }
+        }
+        if (!alldone) barf(sb, n, indent, false, 1, loc);
+    }
+
+
+
     // FIXME
     private static HashSet<GSS.Phase.Node> touched = new HashSet<GSS.Phase.Node>();
-    static <Tok> void complain(GSS.Phase<Tok>.Node n, HashMap<String,HashSet<String>> errors, boolean force) {
+    static <Tok> void complain(GSS.Phase<Tok>.Node n, HashMap<String,HashSet<String>> errors, boolean force, int indent) {
         if (touched.contains(n)) return;
         touched.add(n);
         for(Position p : n.state) {
-            if (((p.isFirst() || p.isLast()) && !force)/* || p.owner().name==null*/) {
+            //if (!p.isLast() && !p.next().isLast()) continue;
+            if (((p.isFirst() || p.isLast()) && !force)/* || p.owner().name==null*/ ||
+                !important(p)) {
                 for(Node n2 : n.parents())
-                    complain(n2, errors, force | p.isFirst());
+                    complain(n2, errors, force /*| p.isFirst()*/, indent);
             } else {
                 String seqname = p.owner()/*.name*/+"";
                 HashSet<String> hs = errors.get(seqname);
                 if (hs==null) errors.put(seqname, hs = new HashSet<String>());
-                hs.add(p.element()+"");
+                String s = "";
+                hs.add(" "+p.element()+"");
             }
         }
     }
 
     static String el(Object e) {
         String s = e.toString();
-        if (s.length()==0 || s.charAt(0)!='\"' || s.charAt(s.length()-1)!='\"') return /*ANSI.yellow(s)*/s;
+        if (s.length()==0 || s.charAt(0)!='\"' || s.charAt(s.length()-1)!='\"') return ANSI.yellow(s);
         s = s.substring(1);
         s = s.substring(0, s.length()-1);
         StringBuffer ret = new StringBuffer();
@@ -79,36 +127,95 @@ public class ParseFailed extends Exception {
             if (s.charAt(i)=='\\' && i<s.length()-1) ret.append(s.charAt(++i));
             else ret.append(s);
         }
-        return /*ANSI.purple(ret.toString())*/ret.toString();
+        return ANSI.purple(ret.toString());
     }
-    static String error(String message, Object token, Iterable<Node> nodes) {
+
+    static void error(String message,
+                      Input.Location loc,
+                      Object token,
+                      Iterable<Node> nodes,
+                      Input.Region region,
+                      Input input,
+                      GSS gss) throws ParseFailed{
         String lookAhead = token==null ? "<EOF>" : token.toString();
         StringBuffer ret = new StringBuffer();
-        ret.append("\n  ");
-        ret.append(message);
+        ret.append(ANSI.bold(ANSI.red(message)));
+        if (token != null) {
+            ret.append(" \'");
+            ret.append(ANSI.cyan(StringUtil.escapify(token+"", "\\\'\r\n")));
+            ret.append("\'");
+        }
+        ret.append(" at ");
+        ret.append(ANSI.yellow(region+""));
+        if (input != null) {
+            ret.append('\n');
+            ret.append("     text: ");
+            int budget = 60;
+            String second = input.showRegion(region);
+            budget -= second.length();
+            Input.Location after = region.getEnd();
+            for(int i=0; i<10; i++) after = after.next() == null ? after : after.next();
+            String third = input.showRegion(region.getEnd().createRegion(after));
+            budget -= third.length();
+            Input.Location before = region.getStart();
+            for(int i=0; i<budget; i++) before = before.prev() == null ? before : before.prev();
+            String first = input.showRegion(before.createRegion(region.getStart()));
+            ret.append(ANSI.cyan(first));
+            ret.append(ANSI.invert(ANSI.red(second)));
+            ret.append(ANSI.cyan(third));
+            /*
+            ret.append('\n');
+            ret.append("           ");
+            for(int i=0; i<first.length(); i++) ret.append(' ');
+            for(int i=0; i<second.length(); i++) ret.append(ANSI.red("^"));
+            */
+        }
+        HashMap<Element,Input.Location> hm = new HashMap<Element,Input.Location>();
+        for(Node no : nodes)
+            barf(hm, no, 0, false, /*region.getStart()*/loc);
+        ret.append("\n expected: ");
+        Set<Element> hs = hm.keySet();
+        if (hs.size() == 1) {
+            ret.append(hs.iterator().next());
+        } else {
+            int i=0;
+            for(Element s : hs) {
+                Input.Location loc2 = hm.get(s);
+                if (i==0) {
+                    ret.append("" + ANSI.purple(s));
+                } else {
+                    ret.append("\n        or " + ANSI.purple(s));
+                }
+                Input.Region reg = loc2.createRegion(region.getStart());
+                ret.append(" to match \"" + ANSI.cyan(input.showRegion(reg)) + "\" at " + ANSI.yellow(reg));
+                i++;
+            }
+        }
         /*
+        ret.append("\n  The author of SBP apologizes for the these nearly-useless error messages:\n\n");
         HashMap<String,HashSet<String>> errors = new HashMap<String,HashSet<String>>();
         for(Node n : nodes) {
             //System.out.println(n.state);
-            complain(n, errors, false);
+            complain(n, errors, false, 0);
         }
         for(String s : errors.keySet()) {
             ret.append("    while parsing " + ANSI.yellow(s));
             HashSet<String> hs = errors.get(s);
-            if (hs.size()==1) ret.append(" expected " + ANSI.yellow(el(hs.iterator().next())) + "\n");
+
+            if (hs.size()==1) ret.append("\n      expected " + ANSI.yellow(el(hs.iterator().next())) + "\n\n");
             else {
-                ret.append(" expected ");
+                ret.append("\n      expected ");
                 boolean first = true;
                 for(String s2 : hs) {
                     if (!first) ret.append(" or ");
                     first = false;
                     ret.append(ANSI.yellow(el(s2)));
                 }
-                ret.append("\n");
+                ret.append("\n\n");
             }
         }
         */
-        return ret.toString();
+        throw new ParseFailed(ret.toString(), region, input, gss);
     }
 
 }
diff --git a/src/edu/berkeley/sbp/Union.java b/src/edu/berkeley/sbp/Union.java
index 51002ab..5ff00d6 100644
--- a/src/edu/berkeley/sbp/Union.java
+++ b/src/edu/berkeley/sbp/Union.java
@@ -19,8 +19,8 @@ import java.lang.ref.*;
  */
 public class Union extends Element implements Iterable<Sequence> {
 
-    private final String name;
-    private final boolean synthetic;
+    /*private*/ final String name;
+    /*private*/ final boolean synthetic;
     private boolean viewed = false;
 
     private final List<Sequence> alternatives = new ArrayList<Sequence>();
diff --git a/src/edu/berkeley/sbp/chr/CharInput.java b/src/edu/berkeley/sbp/chr/CharInput.java
index 65b2b3e..b6a175d 100644
--- a/src/edu/berkeley/sbp/chr/CharInput.java
+++ b/src/edu/berkeley/sbp/chr/CharInput.java
@@ -48,6 +48,8 @@ public class CharInput extends Cartesian.Input<Character> {
         Cartesian.Region r = (Cartesian.Region)rc;
         int start = r.getStart().getScalar()+1;
         int end = r.getEnd().getScalar()+1;
+        if (start < 0) start = 0;
+        if (end < start) end = start;
         if (end > cache.length()) end = cache.length();
         String ret;
         if (end-start < 60) ret = cache.substring(start, end);
diff --git a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
index 40f3e39..cae45c0 100644
--- a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
+++ b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
@@ -79,9 +79,8 @@ public class MetaGrammarBindings extends AnnotationGrammarBindings {
                 Seq[] group = sequences[i];
                 Union u2 = new Union(null, false);
                 if (sequences.length==1) u2 = u;
-                for(int j=0; j<group.length; j++) {
+                for(int j=0; j<group.length; j++)
                     group[j].build(cx, u2, cnt);
-                }
                 if (sequences.length==1) break;
                 Sequence seq = Sequence.create(u2);
                 for(Sequence s : bad2) seq = seq.andnot(s);
diff --git a/src/edu/berkeley/sbp/util/ANSI.java b/src/edu/berkeley/sbp/util/ANSI.java
index a3304f0..0ffe126 100644
--- a/src/edu/berkeley/sbp/util/ANSI.java
+++ b/src/edu/berkeley/sbp/util/ANSI.java
@@ -8,12 +8,14 @@ public class ANSI {
     //public static String red(Object o) { return o+""; }
     //public static String green(Object o) { return "\033[32m"+o+"\033[0m"; }
     public static String green(Object o) { return o+""; }
-    //public static String yellow(Object o) { return "\033[33m"+o+"\033[0m"; }
-    public static String yellow(Object o) { return o+""; }
+    public static String yellow(Object o) { return "\033[33m"+o+"\033[0m"; }
+    //public static String yellow(Object o) { return o+""; }
     //public static String blue(Object o) { return "\033[34m"+o+"\033[0m"; }
     public static String blue(Object o) { return o+""; }
-    //public static String purple(Object o) { return "\033[35m"+o+"\033[0m"; }
-    public static String purple(Object o) { return o+""; }
-    //public static String cyan(Object o) { return "\033[36m"+o+"\033[0m"; }
-    public static String cyan(Object o) { return o+""; }
+    public static String purple(Object o) { return "\033[35m"+o+"\033[0m"; }
+    //public static String purple(Object o) { return o+""; }
+    public static String cyan(Object o) { return "\033[36m"+o+"\033[0m"; }
+    //public static String cyan(Object o) { return o+""; }
+    public static String invert(Object o) { return "\033[7m"+o+"\033[0m"; }
+    public static String bold(Object o) { return "\033[1m"+o+"\033[0m"; }
 }
diff --git a/tests/java15.g b/tests/java15.g
index f89658e..3b33aca 100644
--- a/tests/java15.g
+++ b/tests/java15.g
@@ -23,7 +23,7 @@ ClassDecl     = Class::     Modifiers "class"     TypeDecl ClassBody /ws
 InterfaceDecl = Interface:: Modifiers "interface" TypeDecl ClassBody /ws
 
 TypeDecl =                   Identifier
-         | GenericTypeDecl:: Identifier "<" (TypeArg +/ Comma) ">" /ws
+         | GenericTypeDecl:: Identifier "<" (TypeArg +/ comma) ">" /ws
 
 TypeArg =                Identifier
         | Extends::      Identifier "extends" Type  /ws
@@ -43,17 +43,17 @@ MethodDecl = Method:: MethodHeader (";" | MethodBody) /ws
 MethodHeader  = MethodHeader:: Modifiers Type Identifier Args /ws
 MethodBody    = "{" "}" /ws
 
-Args = "(" (Arg+/Comma) ")" /ws
+Args = "(" (Arg+/comma) ")" /ws
      | "(" ws! ")"
 Arg = Arg:: Type Identifier /ws
 
 Type        = BareType | GenericType | ArrayType
 BareType    = Type::        TypeName | "boolean" | "int" | "double" | "float" | "char" | "short" | "long" | "void"
-GenericType = GenericType:: TypeName "<" (Type+/Comma) ">" /ws
+GenericType = GenericType:: TypeName "<" (Type+/comma) ">" /ws
 ArrayType   = ArrayOf::     (BareType | GenericType) "[]" /ws
 
 ws = [\r\n ]**
-Comma = ws! "," ws!
+comma = ws! "," ws!
 
 JavaLetter = [a-zA-Z_$]
 Identifier = JavaLetter++
diff --git a/tests/java15.test b/tests/java15.test
index b52f1fa..a8efc19 100644
--- a/tests/java15.test
+++ b/tests/java15.test
@@ -3,7 +3,7 @@ import foo.bar;
 
 public class Baz < A extends Object , Q super Foo<Bar<Baz>,Bop> > {
 
-  public void foo(int x, char y, Bop<Baz<M>> q) {
+  public voider adsffbid foo(int x, char y, Bop<Baz<M>> q) {
   }
 
   protected abstract int bar(int c);