// THIS FILE IS ALSO AN APPJET MODULE: etherpad.collab.ace.easysync2_tests
// %APPJET%: import("etherpad.collab.ace.easysync2.*")

/**
 * Copyright 2009 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS-IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

function runTests() {

  function print(str) {
    java.lang.System.out.println(str);
  }

  function assert(code, optMsg) {
    if (! eval(code)) throw new Error("FALSE: "+(optMsg || code));
  }
  function literal(v) {
    if ((typeof v) == "string") {
      return '"'+v.replace(/[\\\"]/g, '\\$1').replace(/\n/g, '\\n')+'"';
    }
    else return v.toSource();
  }
  function assertEqualArrays(a, b) {
    assert(literal(a)+".toSource() == "+literal(b)+".toSource()");
  }
  function assertEqualStrings(a, b) {
    assert(literal(a)+" == "+literal(b));
  }

  function throughIterator(opsStr) {
    var iter = Changeset.opIterator(opsStr);
    var assem = Changeset.opAssembler();
    while (iter.hasNext()) {
      assem.append(iter.next());
    }
    return assem.toString();
  }

  function throughSmartAssembler(opsStr) {
    var iter = Changeset.opIterator(opsStr);
    var assem = Changeset.smartOpAssembler();
    while (iter.hasNext()) {
      assem.append(iter.next());
    }
    assem.endDocument();
    return assem.toString();
  }

  (function() {
    print("> throughIterator");
    var x = '-c*3*4+6|3=az*asdf0*1*2*3+1=1-1+1*0+1=1-1+1|c=c-1';
    assert("throughIterator("+literal(x)+") == "+literal(x));
  })();

  (function() {
    print("> throughSmartAssembler");
    var x = '-c*3*4+6|3=az*asdf0*1*2*3+1=1-1+1*0+1=1-1+1|c=c-1';
    assert("throughSmartAssembler("+literal(x)+") == "+literal(x));
  })();

  function applyMutations(mu, arrayOfArrays) {
    arrayOfArrays.forEach(function (a) {
      var result = mu[a[0]].apply(mu, a.slice(1));
      if (a[0] == 'remove' && a[3]) {
        assertEqualStrings(a[3], result);
      }
    });
  }

  function mutationsToChangeset(oldLen, arrayOfArrays) {
    var assem = Changeset.smartOpAssembler();
    var op = Changeset.newOp();
    var bank = Changeset.stringAssembler();
    var oldPos = 0;
    var newLen = 0;
    arrayOfArrays.forEach(function (a) {
      if (a[0] == 'skip') {
        op.opcode = '=';
        op.chars = a[1];
        op.lines = (a[2] || 0);
        assem.append(op);
        oldPos += op.chars;
        newLen += op.chars;
      }
      else if (a[0] == 'remove') {
        op.opcode = '-';
        op.chars = a[1];
        op.lines = (a[2] || 0);
        assem.append(op);
        oldPos += op.chars;
      }
      else if (a[0] == 'insert') {
        op.opcode = '+';
        bank.append(a[1]);
        op.chars = a[1].length;
        op.lines = (a[2] || 0);
        assem.append(op);
        newLen += op.chars;
      }
    });
    newLen += oldLen - oldPos;
    assem.endDocument();
    return Changeset.pack(oldLen, newLen, assem.toString(),
                          bank.toString());
  }

  function runMutationTest(testId, origLines, muts, correct) {
    print("> runMutationTest#"+testId);
    var lines = origLines.slice();
    var mu = Changeset.textLinesMutator(lines);
    applyMutations(mu, muts);
    mu.close();
    assertEqualArrays(correct, lines);

    var inText = origLines.join('');
    var cs = mutationsToChangeset(inText.length, muts);
    lines = origLines.slice();
    Changeset.mutateTextLines(cs, lines);
    assertEqualArrays(correct, lines);

    var correctText = correct.join('');
    //print(literal(cs));
    var outText = Changeset.applyToText(cs, inText);
    assertEqualStrings(correctText, outText);
  }

  runMutationTest(1, ["apple\n", "banana\n", "cabbage\n", "duffle\n", "eggplant\n"],
                  [['remove',1,0,"a"],['insert',"tu"],['remove',1,0,"p"],['skip',4,1],['skip',7,1],
                   ['insert',"cream\npie\n",2],['skip',2],['insert',"bot"],['insert',"\n",1],
                   ['insert',"bu"],['skip',3],['remove',3,1,"ge\n"],['remove',6,0,"duffle"]],
                  ["tuple\n","banana\n","cream\n","pie\n", "cabot\n","bubba\n","eggplant\n"]);

  runMutationTest(2, ["apple\n", "banana\n", "cabbage\n", "duffle\n", "eggplant\n"],
                  [['remove',1,0,"a"],['remove',1,0,"p"],['insert',"tu"],['skip',11,2],
                   ['insert',"cream\npie\n",2],['skip',2],['insert',"bot"],['insert',"\n",1],
                   ['insert',"bu"],['skip',3],['remove',3,1,"ge\n"],['remove',6,0,"duffle"]],
                  ["tuple\n","banana\n","cream\n","pie\n", "cabot\n","bubba\n","eggplant\n"]);

  runMutationTest(3, ["apple\n", "banana\n", "cabbage\n", "duffle\n", "eggplant\n"],
                  [['remove',6,1,"apple\n"],['skip',15,2],['skip',6],['remove',1,1,"\n"],
                   ['remove',8,0,"eggplant"],['skip',1,1]],
                  ["banana\n","cabbage\n","duffle\n"]);

  runMutationTest(4, ["15\n"],
                  [['skip',1],['insert',"\n2\n3\n4\n",4],['skip',2,1]],
                  ["1\n","2\n","3\n","4\n","5\n"]);

  runMutationTest(5, ["1\n","2\n","3\n","4\n","5\n"],
                  [['skip',1],['remove',7,4,"\n2\n3\n4\n"],['skip',2,1]],
                  ["15\n"]);

  runMutationTest(6, ["123\n","abc\n","def\n","ghi\n","xyz\n"],
                  [['insert',"0"],['skip',4,1],['skip',4,1],['remove',8,2,"def\nghi\n"],['skip',4,1]],
                  ["0123\n", "abc\n", "xyz\n"]);

  runMutationTest(7, ["apple\n", "banana\n", "cabbage\n", "duffle\n", "eggplant\n"],
                  [['remove',6,1,"apple\n"],['skip',15,2,true],['skip',6,0,true],['remove',1,1,"\n"],
                   ['remove',8,0,"eggplant"],['skip',1,1,true]],
                  ["banana\n","cabbage\n","duffle\n"]);

  function poolOrArray(attribs) {
    if (attribs.getAttrib) {
      return attribs; // it's already an attrib pool
    }
    else {
      // assume it's an array of attrib strings to be split and added
      var p = new AttribPool();
      attribs.forEach(function (kv) { p.putAttrib(kv.split(',')); });
      return p;
    }
  }

  function runApplyToAttributionTest(testId, attribs, cs, inAttr, outCorrect) {
    print("> applyToAttribution#"+testId);
    var p = poolOrArray(attribs);
    var result = Changeset.applyToAttribution(
      Changeset.checkRep(cs), inAttr, p);
    assertEqualStrings(outCorrect, result);
  }

  // turn c<b>a</b>ctus\n into a<b>c</b>tusabcd\n
  runApplyToAttributionTest(1, ['bold,', 'bold,true'],
                            "Z:7>3-1*0=1*1=1=3+4$abcd",
                            "+1*1+1|1+5", "+1*1+1|1+8");

  // turn "david\ngreenspan\n" into "<b>david\ngreen</b>\n"
  runApplyToAttributionTest(2, ['bold,', 'bold,true'],
                            "Z:g<4*1|1=6*1=5-4$",
                            "|2+g", "*1|1+6*1+5|1+1");

  (function() {
    print("> mutatorHasMore");
    var lines = ["1\n", "2\n", "3\n", "4\n"];
    var mu;

    mu = Changeset.textLinesMutator(lines);
    assert(mu.hasMore()+' == true');
    mu.skip(8,4);
    assert(mu.hasMore()+' == false');
    mu.close();
    assert(mu.hasMore()+' == false');

    // still 1,2,3,4
    mu = Changeset.textLinesMutator(lines);
    assert(mu.hasMore()+' == true');
    mu.remove(2,1);
    assert(mu.hasMore()+' == true');
    mu.skip(2,1);
    assert(mu.hasMore()+' == true');
    mu.skip(2,1);
    assert(mu.hasMore()+' == true');
    mu.skip(2,1);
    assert(mu.hasMore()+' == false');
    mu.insert("5\n", 1);
    assert(mu.hasMore()+' == false');
    mu.close();
    assert(mu.hasMore()+' == false');

    // 2,3,4,5 now
    mu = Changeset.textLinesMutator(lines);
    assert(mu.hasMore()+' == true');
    mu.remove(6,3);
    assert(mu.hasMore()+' == true');
    mu.remove(2,1);
    assert(mu.hasMore()+' == false');
    mu.insert("hello\n", 1);
    assert(mu.hasMore()+' == false');
    mu.close();
    assert(mu.hasMore()+' == false');

  })();

  function runMutateAttributionTest(testId, attribs, cs, alines, outCorrect) {
    print("> runMutateAttributionTest#"+testId);
    var p = poolOrArray(attribs);
    var alines2 = Array.prototype.slice.call(alines);
    var result = Changeset.mutateAttributionLines(
      Changeset.checkRep(cs), alines2, p);
    assertEqualArrays(outCorrect, alines2);

    print("> runMutateAttributionTest#"+testId+".applyToAttribution");
    function removeQuestionMarks(a) { return a.replace(/\?/g, ''); }
    var inMerged = Changeset.joinAttributionLines(alines.map(removeQuestionMarks));
    var correctMerged = Changeset.joinAttributionLines(outCorrect.map(removeQuestionMarks));
    var mergedResult = Changeset.applyToAttribution(cs, inMerged, p);
    assertEqualStrings(correctMerged, mergedResult);
  }

  // turn 123\n 456\n 789\n into 123\n 4<b>5</b>6\n 789\n
  runMutateAttributionTest(1, ["bold,true"], "Z:c>0|1=4=1*0=1$", ["|1+4", "|1+4", "|1+4"],
                           ["|1+4", "+1*0+1|1+2", "|1+4"]);

  // make a document bold
  runMutateAttributionTest(2, ["bold,true"], "Z:c>0*0|3=c$", ["|1+4", "|1+4", "|1+4"],
                           ["*0|1+4", "*0|1+4", "*0|1+4"]);

  // clear bold on document
  runMutateAttributionTest(3, ["bold,","bold,true"], "Z:c>0*0|3=c$",
                           ["*1+1+1*1+1|1+1", "+1*1+1|1+2", "*1+1+1*1+1|1+1"],
                           ["|1+4", "|1+4", "|1+4"]);

  // add a character on line 3 of a document with 5 blank lines, and make sure
  // the optimization that skips purely-kept lines is working; if any attribution string
  // with a '?' is parsed it will cause an error.
  runMutateAttributionTest(4, ['foo,bar','line,1','line,2','line,3','line,4','line,5'],
                           "Z:5>1|2=2+1$x",
                           ["?*1|1+1", "?*2|1+1", "*3|1+1", "?*4|1+1", "?*5|1+1"],
                           ["?*1|1+1", "?*2|1+1", "+1*3|1+1", "?*4|1+1", "?*5|1+1"]);

  var testPoolWithChars = (function() {
    var p = new AttribPool();
    p.putAttrib(['char','newline']);
    for(var i=1;i<36;i++) {
      p.putAttrib(['char',Changeset.numToString(i)]);
    }
    p.putAttrib(['char','']);
    return p;
  })();

  // based on runMutationTest#1
  runMutateAttributionTest(5, testPoolWithChars,
                           "Z:11>7-2*t+1*u+1|2=b|2+a=2*b+1*o+1*t+1*0|1+1*b+1*u+1=3|1-3-6$"+
                           "tucream\npie\nbot\nbu",
                           ["*a+1*p+2*l+1*e+1*0|1+1",
                            "*b+1*a+1*n+1*a+1*n+1*a+1*0|1+1",
                            "*c+1*a+1*b+2*a+1*g+1*e+1*0|1+1",
                            "*d+1*u+1*f+2*l+1*e+1*0|1+1",
                            "*e+1*g+2*p+1*l+1*a+1*n+1*t+1*0|1+1"],
                           ["*t+1*u+1*p+1*l+1*e+1*0|1+1",
                            "*b+1*a+1*n+1*a+1*n+1*a+1*0|1+1",
                            "|1+6",
                            "|1+4",
                            "*c+1*a+1*b+1*o+1*t+1*0|1+1",
                            "*b+1*u+1*b+2*a+1*0|1+1",
                            "*e+1*g+2*p+1*l+1*a+1*n+1*t+1*0|1+1"]);

  // based on runMutationTest#3
  runMutateAttributionTest(6, testPoolWithChars,
                           "Z:11<f|1-6|2=f=6|1-1-8$",
                           ["*a|1+6", "*b|1+7", "*c|1+8", "*d|1+7", "*e|1+9"],
                           ["*b|1+7", "*c|1+8", "*d+6*e|1+1"]);

  // based on runMutationTest#4
  runMutateAttributionTest(7, testPoolWithChars,
                           "Z:3>7=1|4+7$\n2\n3\n4\n",
                           ["*1+1*5|1+2"],
                           ["*1+1|1+1","|1+2","|1+2","|1+2","*5|1+2"]);

  // based on runMutationTest#5
  runMutateAttributionTest(8, testPoolWithChars,
                           "Z:a<7=1|4-7$",
                           ["*1|1+2","*2|1+2","*3|1+2","*4|1+2","*5|1+2"],
                           ["*1+1*5|1+2"]);

  // based on runMutationTest#6
  runMutateAttributionTest(9, testPoolWithChars,
                           "Z:k<7*0+1*10|2=8|2-8$0",
                           ["*1+1*2+1*3+1|1+1","*a+1*b+1*c+1|1+1",
                            "*d+1*e+1*f+1|1+1","*g+1*h+1*i+1|1+1","?*x+1*y+1*z+1|1+1"],
                           ["*0+1|1+4", "|1+4", "?*x+1*y+1*z+1|1+1"]);

  runMutateAttributionTest(10, testPoolWithChars,
                           "Z:6>4=1+1=1+1|1=1+1=1*0+1$abcd",
                           ["|1+3", "|1+3"],
                           ["|1+5", "+2*0+1|1+2"]);


  runMutateAttributionTest(11, testPoolWithChars,
                           "Z:s>1|1=4=6|1+1$\n",
                           ["*0|1+4", "*0|1+8", "*0+5|1+1", "*0|1+1", "*0|1+5", "*0|1+1", "*0|1+1", "*0|1+1", "|1+1"],
                           ["*0|1+4", "*0+6|1+1", "*0|1+2", "*0+5|1+1", "*0|1+1", "*0|1+5", "*0|1+1", "*0|1+1", "*0|1+1", "|1+1"]);

  function randomInlineString(len, rand) {
    var assem = Changeset.stringAssembler();
    for(var i=0;i<len;i++) {
      assem.append(String.fromCharCode(rand.nextInt(26) + 97));
    }
    return assem.toString();
  }

  function randomMultiline(approxMaxLines, approxMaxCols, rand) {
    var numParts = rand.nextInt(approxMaxLines*2)+1;
    var txt = Changeset.stringAssembler();
    txt.append(rand.nextInt(2) ? '\n' : '');
    for(var i=0;i<numParts;i++) {
      if ((i % 2) == 0) {
        if (rand.nextInt(10)) {
          txt.append(randomInlineString(rand.nextInt(approxMaxCols)+1, rand));
        }
        else {
          txt.append('\n');
        }
      }
      else {
        txt.append('\n');
      }
    }
    return txt.toString();
  }

  function randomStringOperation(numCharsLeft, rand) {
    var result;
    switch(rand.nextInt(9)) {
    case 0: {
      // insert char
      result = {insert: randomInlineString(1, rand)};
      break;
    }
    case 1: {
      // delete char
      result = {remove: 1};
      break;
    }
    case 2: {
      // skip char
      result = {skip: 1};
      break;
    }
    case 3: {
      // insert small
      result = {insert: randomInlineString(rand.nextInt(4)+1, rand)};
      break;
    }
    case 4: {
      // delete small
      result = {remove: rand.nextInt(4)+1};
      break;
    }
    case 5: {
      // skip small
      result = {skip: rand.nextInt(4)+1};
      break;
    }
    case 6: {
      // insert multiline;
      result = {insert: randomMultiline(5, 20, rand)};
      break;
    }
    case 7: {
      // delete multiline
      result = {remove: Math.round(numCharsLeft * rand.nextDouble() * rand.nextDouble()) };
      break;
    }
    case 8: {
      // skip multiline
      result = {skip: Math.round(numCharsLeft * rand.nextDouble() * rand.nextDouble()) };
      break;
    }
    case 9: {
      // delete to end
      result = {remove: numCharsLeft};
      break;
    }
    case 10: {
      // skip to end
      result = {skip: numCharsLeft};
      break;
    }
    }
    var maxOrig = numCharsLeft - 1;
    if ('remove' in result) {
      result.remove = Math.min(result.remove, maxOrig);
    }
    else if ('skip' in result) {
      result.skip = Math.min(result.skip, maxOrig);
    }
    return result;
  }

  function randomTwoPropAttribs(opcode, rand) {
    // assumes attrib pool like ['apple,','apple,true','banana,','banana,true']
    if (opcode == '-' || rand.nextInt(3)) {
      return '';
    }
    else if (rand.nextInt(3)) {
      if (opcode == '+' || rand.nextInt(2)) {
        return '*'+Changeset.numToString(rand.nextInt(2)*2+1);
      }
      else {
        return '*'+Changeset.numToString(rand.nextInt(2)*2);
      }
    }
    else {
      if (opcode == '+' || rand.nextInt(4) == 0) {
        return '*1*3';
      }
      else {
        return ['*0*2', '*0*3', '*1*2'][rand.nextInt(3)];
      }
    }
  }

  function randomTestChangeset(origText, rand, withAttribs) {
    var charBank = Changeset.stringAssembler();
    var textLeft = origText; // always keep final newline
    var outTextAssem = Changeset.stringAssembler();
    var opAssem = Changeset.smartOpAssembler();
    var oldLen = origText.length;

    var nextOp = Changeset.newOp();
    function appendMultilineOp(opcode, txt) {
      nextOp.opcode = opcode;
      if (withAttribs) {
        nextOp.attribs = randomTwoPropAttribs(opcode, rand);
      }
      txt.replace(/\n|[^\n]+/g, function (t) {
        if (t == '\n') {
          nextOp.chars = 1;
          nextOp.lines = 1;
          opAssem.append(nextOp);
        }
        else {
          nextOp.chars = t.length;
          nextOp.lines = 0;
          opAssem.append(nextOp);
        }
        return '';
      });
    }

    function doOp() {
      var o = randomStringOperation(textLeft.length, rand);
      if (o.insert) {
        var txt = o.insert;
        charBank.append(txt);
        outTextAssem.append(txt);
        appendMultilineOp('+', txt);
      }
      else if (o.skip) {
        var txt = textLeft.substring(0, o.skip);
        textLeft = textLeft.substring(o.skip);
        outTextAssem.append(txt);
        appendMultilineOp('=', txt);
      }
      else if (o.remove) {
        var txt = textLeft.substring(0, o.remove);
        textLeft = textLeft.substring(o.remove);
        appendMultilineOp('-', txt);
      }
    }

    while (textLeft.length > 1) doOp();
    for(var i=0;i<5;i++) doOp(); // do some more (only insertions will happen)

    var outText = outTextAssem.toString()+'\n';
    opAssem.endDocument();
    var cs = Changeset.pack(oldLen, outText.length, opAssem.toString(), charBank.toString());
    Changeset.checkRep(cs);
    return [cs, outText];
  }

  function testCompose(randomSeed) {
    var rand = new java.util.Random(randomSeed);
    print("> testCompose#"+randomSeed);

    var p = new AttribPool();

    var startText = randomMultiline(10, 20, rand)+'\n';

    var x1 = randomTestChangeset(startText, rand);
    var change1 = x1[0];
    var text1 = x1[1];

    var x2 = randomTestChangeset(text1, rand);
    var change2 = x2[0];
    var text2 = x2[1];

    var x3 = randomTestChangeset(text2, rand);
    var change3 = x3[0];
    var text3 = x3[1];

    //print(literal(Changeset.toBaseTen(startText)));
    //print(literal(Changeset.toBaseTen(change1)));
    //print(literal(Changeset.toBaseTen(change2)));
    var change12 = Changeset.checkRep(Changeset.compose(change1, change2, p));
    var change23 = Changeset.checkRep(Changeset.compose(change2, change3, p));
    var change123 = Changeset.checkRep(Changeset.compose(change12, change3, p));
    var change123a = Changeset.checkRep(Changeset.compose(change1, change23, p));
    assertEqualStrings(change123, change123a);

    assertEqualStrings(text2, Changeset.applyToText(change12, startText));
    assertEqualStrings(text3, Changeset.applyToText(change23, text1));
    assertEqualStrings(text3, Changeset.applyToText(change123, startText));
  }

  for(var i=0;i<30;i++) testCompose(i);

  (function simpleComposeAttributesTest() {
    print("> simpleComposeAttributesTest");
    var p = new AttribPool();
    p.putAttrib(['bold','']);
    p.putAttrib(['bold','true']);
    var cs1 = Changeset.checkRep("Z:2>1*1+1*1=1$x");
    var cs2 = Changeset.checkRep("Z:3>0*0|1=3$");
    var cs12 = Changeset.checkRep(Changeset.compose(cs1, cs2, p));
    assertEqualStrings("Z:2>1+1*0|1=2$x", cs12);
  })();

  (function followAttributesTest() {
    var p = new AttribPool();
    p.putAttrib(['x','']);
    p.putAttrib(['x','abc']);
    p.putAttrib(['x','def']);
    p.putAttrib(['y','']);
    p.putAttrib(['y','abc']);
    p.putAttrib(['y','def']);

    function testFollow(a, b, afb, bfa, merge) {
      assertEqualStrings(afb, Changeset.followAttributes(a, b, p));
      assertEqualStrings(bfa, Changeset.followAttributes(b, a, p));
      assertEqualStrings(merge, Changeset.composeAttributes(a, afb, true, p));
      assertEqualStrings(merge, Changeset.composeAttributes(b, bfa, true, p));
    }

    testFollow('', '', '', '', '');
    testFollow('*0', '', '', '*0', '*0');
    testFollow('*0', '*0', '', '', '*0');
    testFollow('*0', '*1', '', '*0', '*0');
    testFollow('*1', '*2', '', '*1', '*1');
    testFollow('*0*1', '', '', '*0*1', '*0*1');
    testFollow('*0*4', '*2*3', '*3', '*0', '*0*3');
    testFollow('*0*4', '*2', '', '*0*4', '*0*4');
  })();

  function testFollow(randomSeed) {
    var rand = new java.util.Random(randomSeed + 1000);
    print("> testFollow#"+randomSeed);

    var p = new AttribPool();

    var startText = randomMultiline(10, 20, rand)+'\n';

    var cs1 = randomTestChangeset(startText, rand)[0];
    var cs2 = randomTestChangeset(startText, rand)[0];

    var afb = Changeset.checkRep(Changeset.follow(cs1, cs2, false, p));
    var bfa = Changeset.checkRep(Changeset.follow(cs2, cs1, true, p));

    var merge1 = Changeset.checkRep(Changeset.compose(cs1, afb));
    var merge2 = Changeset.checkRep(Changeset.compose(cs2, bfa));

    assertEqualStrings(merge1, merge2);
  }

  for(var i=0;i<30;i++) testFollow(i);

  function testSplitJoinAttributionLines(randomSeed) {
    var rand = new java.util.Random(randomSeed + 2000);
    print("> testSplitJoinAttributionLines#"+randomSeed);

    var doc = randomMultiline(10, 20, rand)+'\n';

    function stringToOps(str) {
      var assem = Changeset.mergingOpAssembler();
      var o = Changeset.newOp('+');
      o.chars = 1;
      for(var i=0;i<str.length;i++) {
        var c = str.charAt(i);
        o.lines = (c == '\n' ? 1 : 0);
        o.attribs = (c == 'a' || c == 'b' ? '*'+c : '');
        assem.append(o);
      }
      return assem.toString();
    }

    var theJoined = stringToOps(doc);
    var theSplit = doc.match(/[^\n]*\n/g).map(stringToOps);

    assertEqualArrays(theSplit, Changeset.splitAttributionLines(theJoined, doc));
    assertEqualStrings(theJoined, Changeset.joinAttributionLines(theSplit));
  }

  for(var i=0;i<10;i++) testSplitJoinAttributionLines(i);

  (function testMoveOpsToNewPool() {
    print("> testMoveOpsToNewPool");

    var pool1 = new AttribPool();
    var pool2 = new AttribPool();

    pool1.putAttrib(['baz','qux']);
    pool1.putAttrib(['foo','bar']);

    pool2.putAttrib(['foo','bar']);

    assertEqualStrings(Changeset.moveOpsToNewPool('Z:1>2*1+1*0+1$ab', pool1, pool2), 'Z:1>2*0+1*1+1$ab');
    assertEqualStrings(Changeset.moveOpsToNewPool('*1+1*0+1', pool1, pool2), '*0+1*1+1');
  })();


  (function testMakeSplice() {
    print("> testMakeSplice");

    var t = "a\nb\nc\n";
    var t2 = Changeset.applyToText(Changeset.makeSplice(t, 5, 0, "def"), t);
    assertEqualStrings("a\nb\ncdef\n", t2);

  })();

  (function testToSplices() {
    print("> testToSplices");

    var cs = Changeset.checkRep('Z:z>9*0=1=4-3+9=1|1-4-4+1*0+a$123456789abcdefghijk');
    var correctSplices = [[5, 8, "123456789"], [9, 17, "abcdefghijk"]];
    assertEqualArrays(correctSplices, Changeset.toSplices(cs));
  })();

  function testCharacterRangeFollow(testId, cs, oldRange, insertionsAfter, correctNewRange) {
    print("> testCharacterRangeFollow#"+testId);

    var cs = Changeset.checkRep(cs);
    assertEqualArrays(correctNewRange, Changeset.characterRangeFollow(cs, oldRange[0], oldRange[1],
                                                                     insertionsAfter));

  }

  testCharacterRangeFollow(1, 'Z:z>9*0=1=4-3+9=1|1-4-4+1*0+a$123456789abcdefghijk',
                           [7, 10],  false, [14, 15]);
  testCharacterRangeFollow(2, "Z:bc<6|x=b4|2-6$", [400, 407], false, [400, 401]);
  testCharacterRangeFollow(3, "Z:4>0-3+3$abc", [0,3], false, [3,3]);
  testCharacterRangeFollow(4, "Z:4>0-3+3$abc", [0,3], true, [0,0]);
  testCharacterRangeFollow(5, "Z:5>1+1=1-3+3$abcd", [1,4], false, [5,5]);
  testCharacterRangeFollow(6, "Z:5>1+1=1-3+3$abcd", [1,4], true, [2,2]);
  testCharacterRangeFollow(7, "Z:5>1+1=1-3+3$abcd", [0,6], false, [1,7]);
  testCharacterRangeFollow(8, "Z:5>1+1=1-3+3$abcd", [0,3], false, [1,2]);
  testCharacterRangeFollow(9, "Z:5>1+1=1-3+3$abcd", [2,5], false, [5,6]);
  testCharacterRangeFollow(10, "Z:2>1+1$a", [0,0], false, [1,1]);
  testCharacterRangeFollow(11, "Z:2>1+1$a", [0,0], true, [0,0]);

  (function testOpAttributeValue() {
    print("> testOpAttributeValue");

    var p = new AttribPool();
    p.putAttrib(['name','david']);
    p.putAttrib(['color','green']);

    assertEqualStrings("david", Changeset.opAttributeValue(Changeset.stringOp('*0*1+1'), 'name', p));
    assertEqualStrings("david", Changeset.opAttributeValue(Changeset.stringOp('*0+1'), 'name', p));
    assertEqualStrings("", Changeset.opAttributeValue(Changeset.stringOp('*1+1'), 'name', p));
    assertEqualStrings("", Changeset.opAttributeValue(Changeset.stringOp('+1'), 'name', p));
    assertEqualStrings("green", Changeset.opAttributeValue(Changeset.stringOp('*0*1+1'), 'color', p));
    assertEqualStrings("green", Changeset.opAttributeValue(Changeset.stringOp('*1+1'), 'color', p));
    assertEqualStrings("", Changeset.opAttributeValue(Changeset.stringOp('*0+1'), 'color', p));
    assertEqualStrings("", Changeset.opAttributeValue(Changeset.stringOp('+1'), 'color', p));
  })();

  function testAppendATextToAssembler(testId, atext, correctOps) {
    print("> testAppendATextToAssembler#"+testId);

    var assem = Changeset.smartOpAssembler();
    Changeset.appendATextToAssembler(atext, assem);
    assertEqualStrings(correctOps, assem.toString());
  }

  testAppendATextToAssembler(1, {text:"\n", attribs:"|1+1"}, "");
  testAppendATextToAssembler(2, {text:"\n\n", attribs:"|2+2"}, "|1+1");
  testAppendATextToAssembler(3, {text:"\n\n", attribs:"*x|2+2"}, "*x|1+1");
  testAppendATextToAssembler(4, {text:"\n\n", attribs:"*x|1+1|1+1"}, "*x|1+1");
  testAppendATextToAssembler(5, {text:"foo\n", attribs:"|1+4"}, "+3");
  testAppendATextToAssembler(6, {text:"\nfoo\n", attribs:"|2+5"}, "|1+1+3");
  testAppendATextToAssembler(7, {text:"\nfoo\n", attribs:"*x|2+5"}, "*x|1+1*x+3");
  testAppendATextToAssembler(8, {text:"\n\n\nfoo\n", attribs:"|2+2*x|2+5"}, "|2+2*x|1+1*x+3");

  function testMakeAttribsString(testId, pool, opcode, attribs, correctString) {
    print("> testMakeAttribsString#"+testId);

    var p = poolOrArray(pool);
    var str = Changeset.makeAttribsString(opcode, attribs, p);
    assertEqualStrings(correctString, str);
  }

  testMakeAttribsString(1, ['bold,'], '+', [['bold','']], '');
  testMakeAttribsString(2, ['abc,def','bold,'], '=', [['bold','']], '*1');
  testMakeAttribsString(3, ['abc,def','bold,true'], '+', [['abc','def'],['bold','true']], '*0*1');
  testMakeAttribsString(4, ['abc,def','bold,true'], '+', [['bold','true'],['abc','def']], '*0*1');

  function testSubattribution(testId, astr, start, end, correctOutput) {
    print("> testSubattribution#"+testId);

    var str = Changeset.subattribution(astr, start, end);
    assertEqualStrings(correctOutput, str);
  }

  testSubattribution(1, "+1", 0, 0, "");
  testSubattribution(2, "+1", 0, 1, "+1");
  testSubattribution(3, "+1", 0, undefined, "+1");
  testSubattribution(4, "|1+1", 0, 0, "");
  testSubattribution(5, "|1+1", 0, 1, "|1+1");
  testSubattribution(6, "|1+1", 0, undefined, "|1+1");
  testSubattribution(7, "*0+1", 0, 0, "");
  testSubattribution(8, "*0+1", 0, 1, "*0+1");
  testSubattribution(9, "*0+1", 0, undefined, "*0+1");
  testSubattribution(10, "*0|1+1", 0, 0, "");
  testSubattribution(11, "*0|1+1", 0, 1, "*0|1+1");
  testSubattribution(12, "*0|1+1", 0, undefined, "*0|1+1");
  testSubattribution(13, "*0+2+1*1+3", 0, 1, "*0+1");
  testSubattribution(14, "*0+2+1*1+3", 0, 2, "*0+2");
  testSubattribution(15, "*0+2+1*1+3", 0, 3, "*0+2+1");
  testSubattribution(16, "*0+2+1*1+3", 0, 4, "*0+2+1*1+1");
  testSubattribution(17, "*0+2+1*1+3", 0, 5, "*0+2+1*1+2");
  testSubattribution(18, "*0+2+1*1+3", 0, 6, "*0+2+1*1+3");
  testSubattribution(19, "*0+2+1*1+3", 0, 7, "*0+2+1*1+3");
  testSubattribution(20, "*0+2+1*1+3", 0, undefined, "*0+2+1*1+3");
  testSubattribution(21, "*0+2+1*1+3", 1, undefined, "*0+1+1*1+3");
  testSubattribution(22, "*0+2+1*1+3", 2, undefined, "+1*1+3");
  testSubattribution(23, "*0+2+1*1+3", 3, undefined, "*1+3");
  testSubattribution(24, "*0+2+1*1+3", 4, undefined, "*1+2");
  testSubattribution(25, "*0+2+1*1+3", 5, undefined, "*1+1");
  testSubattribution(26, "*0+2+1*1+3", 6, undefined, "");
  testSubattribution(27, "*0+2+1*1|1+3", 0, 1, "*0+1");
  testSubattribution(28, "*0+2+1*1|1+3", 0, 2, "*0+2");
  testSubattribution(29, "*0+2+1*1|1+3", 0, 3, "*0+2+1");
  testSubattribution(30, "*0+2+1*1|1+3", 0, 4, "*0+2+1*1+1");
  testSubattribution(31, "*0+2+1*1|1+3", 0, 5, "*0+2+1*1+2");
  testSubattribution(32, "*0+2+1*1|1+3", 0, 6, "*0+2+1*1|1+3");
  testSubattribution(33, "*0+2+1*1|1+3", 0, 7, "*0+2+1*1|1+3");
  testSubattribution(34, "*0+2+1*1|1+3", 0, undefined, "*0+2+1*1|1+3");
  testSubattribution(35, "*0+2+1*1|1+3", 1, undefined, "*0+1+1*1|1+3");
  testSubattribution(36, "*0+2+1*1|1+3", 2, undefined, "+1*1|1+3");
  testSubattribution(37, "*0+2+1*1|1+3", 3, undefined, "*1|1+3");
  testSubattribution(38, "*0+2+1*1|1+3", 4, undefined, "*1|1+2");
  testSubattribution(39, "*0+2+1*1|1+3", 5, undefined, "*1|1+1");
  testSubattribution(40, "*0+2+1*1|1+3", 1, 5, "*0+1+1*1+2");
  testSubattribution(41, "*0+2+1*1|1+3", 2, 6, "+1*1|1+3");
  testSubattribution(42, "*0+2+1*1+3", 2, 6, "+1*1+3");

  function testFilterAttribNumbers(testId, cs, filter, correctOutput) {
    print("> testFilterAttribNumbers#"+testId);

    var str = Changeset.filterAttribNumbers(cs, filter);
    assertEqualStrings(correctOutput, str);
  }

  testFilterAttribNumbers(1, "*0*1+1+2+3*1+4*2+5*0*2*1*b*c+6",
                          function(n) { return (n%2) == 0; },
                          "*0+1+2+3+4*2+5*0*2*c+6");
  testFilterAttribNumbers(2, "*0*1+1+2+3*1+4*2+5*0*2*1*b*c+6",
                          function(n) { return (n%2) == 1; },
                          "*1+1+2+3*1+4+5*1*b+6");

  function testInverse(testId, cs, lines, alines, pool, correctOutput) {
    print("> testInverse#"+testId);

    pool = poolOrArray(pool);
    var str = Changeset.inverse(Changeset.checkRep(cs), lines, alines, pool);
    assertEqualStrings(correctOutput, str);
  }

  // take "FFFFTTTTT" and apply "-FT--FFTT", the inverse of which is "--F--TT--"
  testInverse(1, "Z:9>0=1*0=1*1=1=2*0=2*1|1=2$", null, ["+4*1+5"], ['bold,','bold,true'],
              "Z:9>0=2*0=1=2*1=2$");

  function testMutateTextLines(testId, cs, lines, correctLines) {
    print("> testMutateTextLines#"+testId);

    var a = lines.slice();
    Changeset.mutateTextLines(cs, a);
    assertEqualArrays(correctLines, a);
  }

  testMutateTextLines(1, "Z:4<1|1-2-1|1+1+1$\nc", ["a\n", "b\n"], ["\n", "c\n"]);
  testMutateTextLines(2, "Z:4>0|1-2-1|2+3$\nc\n", ["a\n", "b\n"], ["\n", "c\n", "\n"]);

  function testInverseRandom(randomSeed) {
    var rand = new java.util.Random(randomSeed + 3000);
    print("> testInverseRandom#"+randomSeed);

    var p = poolOrArray(['apple,','apple,true','banana,','banana,true']);

    var startText = randomMultiline(10, 20, rand)+'\n';
    var alines = Changeset.splitAttributionLines(Changeset.makeAttribution(startText), startText);
    var lines = startText.slice(0,-1).split('\n').map(function(s) { return s+'\n'; });

    var stylifier = randomTestChangeset(startText, rand, true)[0];

    //print(alines.join('\n'));
    Changeset.mutateAttributionLines(stylifier, alines, p);
    //print(stylifier);
    //print(alines.join('\n'));
    Changeset.mutateTextLines(stylifier, lines);

    var changeset = randomTestChangeset(lines.join(''), rand, true)[0];
    var inverseChangeset = Changeset.inverse(changeset, lines, alines, p);

    var origLines = lines.slice();
    var origALines = alines.slice();

    Changeset.mutateTextLines(changeset, lines);
    Changeset.mutateAttributionLines(changeset, alines, p);
    //print(origALines.join('\n'));
    //print(changeset);
    //print(inverseChangeset);
    //print(origLines.map(function(s) { return '1: '+s.slice(0,-1); }).join('\n'));
    //print(lines.map(function(s) { return '2: '+s.slice(0,-1); }).join('\n'));
    //print(alines.join('\n'));
    Changeset.mutateTextLines(inverseChangeset, lines);
    Changeset.mutateAttributionLines(inverseChangeset, alines, p);
    //print(lines.map(function(s) { return '3: '+s.slice(0,-1); }).join('\n'));

    assertEqualArrays(origLines, lines);
    assertEqualArrays(origALines, alines);
  }

  for(var i=0;i<30;i++) testInverseRandom(i);
}