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Merge pull request #9838 from Snuffleupagus/invalid-path-OPS

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Error, rather than warn, once a number of invalid path operators are encountered in `EvaluatorPreprocessor.read` (bug 1443140)
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Tim van der Meij 2018-06-28 23:15:25 +02:00 • committed by GitHub
commit 6fa2c779b5
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4 changed files with 57 additions and 7 deletions
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23
src/core/evaluator.js
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@ -2932,6 +2932,8 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
t['null'] = null;
});
const MAX_INVALID_PATH_OPS = 20;
function EvaluatorPreprocessor(stream, xref, stateManager) {
this.opMap = getOPMap();
// TODO(mduan): pass array of knownCommands rather than this.opMap
@ -2939,6 +2941,7 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
this.parser = new Parser(new Lexer(stream, this.opMap), false, xref);
this.stateManager = stateManager;
this.nonProcessedArgs = [];
this._numInvalidPathOPS = 0;
}
EvaluatorPreprocessor.prototype = {
@ -2976,7 +2979,7 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
// Check that the command is valid
var opSpec = this.opMap[cmd];
if (!opSpec) {
warn('Unknown command "' + cmd + '"');
warn(`Unknown command "${cmd}".`);
continue;
}
@ -3002,18 +3005,28 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
}
if (argsLength < numArgs) {
const partialMsg = `command ${cmd}: expected ${numArgs} args, ` +
`but received ${argsLength} args.`;
// Incomplete path operators, in particular, can result in fairly
// chaotic rendering artifacts. Hence the following heuristics is
// used to error, rather than just warn, once a number of invalid
// path operators have been encountered (fixes bug1443140.pdf).
if ((fn >= OPS.moveTo && fn <= OPS.endPath) && // Path operator
++this._numInvalidPathOPS > MAX_INVALID_PATH_OPS) {
throw new FormatError(`Invalid ${partialMsg}`);
}
// If we receive too few arguments, it's not possible to execute
// the command, hence we skip the command.
warn('Skipping command ' + fn + ': expected ' + numArgs +
' args, but received ' + argsLength + ' args.');
warn(`Skipping ${partialMsg}`);
if (args !== null) {
args.length = 0;
}
continue;
}
} else if (argsLength > numArgs) {
info('Command ' + fn + ': expected [0,' + numArgs +
'] args, but received ' + argsLength + ' args.');
info(`Command ${cmd}: expected [0, ${numArgs}] args, ` +
`but received ${argsLength} args.`);
}
// TODO figure out how to type-check vararg functions