[GR-29996] Implementation of _json module.

PullRequest: graalpython/1684

Author: lukasstadler

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/Python3Core.java

@@ -124,6 +124,9 @@
 import com.oracle.graal.python.builtins.modules.io.StringIOBuiltins;
 import com.oracle.graal.python.builtins.modules.io.TextIOBaseBuiltins;
 import com.oracle.graal.python.builtins.modules.io.TextIOWrapperBuiltins;
+import com.oracle.graal.python.builtins.modules.json.JSONEncoderBuiltins;
+import com.oracle.graal.python.builtins.modules.json.JSONModuleBuiltins;
+import com.oracle.graal.python.builtins.modules.json.JSONScannerBuiltins;
 import com.oracle.graal.python.builtins.modules.lzma.LZMACompressorBuiltins;
 import com.oracle.graal.python.builtins.modules.lzma.LZMADecompressorBuiltins;
 import com.oracle.graal.python.builtins.modules.lzma.LZMAModuleBuiltins;
@@ -438,6 +441,7 @@ private static PythonBuiltins[] initializeBuiltins(boolean nativeAccessAllowed)
                         new CollectionsModuleBuiltins(),
                         new JavaModuleBuiltins(),
                         new JArrayModuleBuiltins(),
+                        new JSONModuleBuiltins(),
                         new SREModuleBuiltins(),
                         new AstModuleBuiltins(),
                         new SelectModuleBuiltins(),
@@ -496,7 +500,11 @@ private static PythonBuiltins[] initializeBuiltins(boolean nativeAccessAllowed)
                         new MultiprocessingModuleBuiltins(),
                         new SemLockBuiltins(),
                         new WarningsModuleBuiltins(),
-                        new GraalPythonModuleBuiltins()));
+                        new GraalPythonModuleBuiltins(),
+
+                        // json
+                        new JSONScannerBuiltins(),
+                        new JSONEncoderBuiltins()));
         if (hasCoverageTool) {
             builtins.add(new TraceModuleBuiltins());
         }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/PythonBuiltinClassType.java

@@ -202,6 +202,10 @@ public enum PythonBuiltinClassType implements TruffleObject {
     PSSLSocket("_SSLSocket", "_ssl"),
     PMemoryBIO("MemoryBIO", "_ssl"),
 
+    // json
+    JSONScanner("Scanner", "_json", Flags.PUBLIC_BASE_WODICT),
+    JSONEncoder("Encoder", "_json", Flags.PUBLIC_BASE_WODICT),
+
     // Errors and exceptions:
 
     // everything after BaseException is considered to be an exception

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/BuiltinConstructors.java

@@ -1158,7 +1158,7 @@ private static Object stringToIntInternal(String num, int base) {
 
         private Object stringToInt(VirtualFrame frame, Object cls, String number, int base, Object origObj) {
             if (base == 0 || base == 10) {
-                Object value = parseSimpleDecimalLiteral(number);
+                Object value = parseSimpleDecimalLiteral(number, 0, number.length());
                 if (value != null) {
                     return createInt(cls, value);
                 }
@@ -1325,23 +1325,23 @@ private static BigInteger asciiToBigInteger(String str, int possibleBase) throws
          * @param arg the string to parse
          * @return parsed integer, long or null if the literal is not simple enough
          */
-        private static Object parseSimpleDecimalLiteral(String arg) {
-            if (arg.isEmpty()) {
+        public static Object parseSimpleDecimalLiteral(String arg, int offset, int remaining) {
+            if (remaining <= 0) {
                 return null;
             }
-            int start = arg.charAt(0) == '-' ? 1 : 0;
-            if (arg.length() <= start || arg.length() > 18 + start) {
+            int start = arg.charAt(offset) == '-' ? 1 : 0;
+            if (remaining <= start || remaining > 18 + start) {
                 return null;
             }
-            if (arg.charAt(start) == '0') {
-                if (arg.length() > start + 1) {
+            if (arg.charAt(start + offset) == '0') {
+                if (remaining > start + 1) {
                     return null;
                 }
                 return 0;
             }
             long value = 0;
-            for (int i = start; i < arg.length(); i++) {
-                char c = arg.charAt(i);
+            for (int i = start; i < remaining; i++) {
+                char c = arg.charAt(i + offset);
                 if (c < '0' || c > '9') {
                     return null;
                 }