TypeScript: Skip Touchstone files.

Author: Max Schaefer

javascript/extractor/src/com/semmle/js/extractor/FileExtractor.java

@@ -1,5 +1,16 @@
 package com.semmle.js.extractor;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileReader;
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import java.util.regex.Pattern;
+
 import com.semmle.js.extractor.ExtractionMetrics.ExtractionPhase;
 import com.semmle.js.extractor.trapcache.CachingTrapWriter;
 import com.semmle.js.extractor.trapcache.ITrapCache;
@@ -10,15 +21,6 @@
 import com.semmle.util.io.WholeIO;
 import com.semmle.util.trap.TrapWriter;
 import com.semmle.util.trap.TrapWriter.Label;
-import java.io.BufferedReader;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileReader;
-import java.io.IOException;
-import java.nio.charset.Charset;
-import java.util.LinkedHashSet;
-import java.util.Set;
-import java.util.regex.Pattern;
 
 /**
  * The file extractor extracts a single file and handles source archive population and TRAP caching;
@@ -167,6 +169,9 @@ private boolean hasBadFileHeader(File f, String lcExt, ExtractorConfig config) {
             return true;
           }
 
+          // Avoid Touchstone files
+          if (isTouchstone(bytes, length)) return true;
+
           return false;
         } catch (IOException e) {
           Exceptions.ignore(e, "Let extractor handle this one.");
@@ -198,6 +203,11 @@ private boolean isXml(byte[] bytes, int length) {
         return false;
       }
 
+      private boolean isTouchstone(byte[] bytes, int length) {
+        String s = new String(bytes, 0, length, StandardCharsets.US_ASCII);
+        return s.startsWith("! TOUCHSTONE file ") || s.startsWith("[Version] 2.0");
+      }
+
       /**
        * Returns true if the byte sequence contains invalid UTF-8 or unprintable ASCII characters.
        */

javascript/extractor/tests/ts/input/touchstone-file.ts

@@ -0,0 +1,2 @@
+! TOUCHSTONE file generated by me
+[Version] 2.0

javascript/extractor/tests/ts/input/touchstone-file2.ts

@@ -0,0 +1 @@
+[Version] 2.0