Merge pull request #18410 from rmuir/painless_parser_performance_bug

painless: fix insanely slow compilation

docs/reference/modules/scripting/painless.asciidoc

@@ -189,7 +189,7 @@ POST hockey/player/1/_update
 {
   "script": {
     "lang": "painless",
-    "inline": "ctx._source.last = params.last ctx._source.nick = params.nick",
+    "inline": "ctx._source.last = params.last; ctx._source.nick = params.nick",
     "params": {
       "last": "gaudreau",
       "nick": "hockey"

modules/lang-painless/src/main/antlr/PainlessParser.g4

@@ -28,15 +28,15 @@ source
 statement
     : IF LP expression RP block ( ELSE block )?                                              # if
     | WHILE LP expression RP ( block | empty )                                               # while
-    | DO block WHILE LP expression RP SEMICOLON?                                             # do
+    | DO block WHILE LP expression RP ( SEMICOLON | EOF )                                    # do
     | FOR LP initializer? SEMICOLON expression? SEMICOLON afterthought? RP ( block | empty ) # for
-    | declaration SEMICOLON?                                                                 # decl
+    | declaration ( SEMICOLON | EOF )                                                        # decl
-    | CONTINUE SEMICOLON?                                                                    # continue
+    | CONTINUE ( SEMICOLON | EOF )                                                           # continue
-    | BREAK SEMICOLON?                                                                       # break
+    | BREAK ( SEMICOLON | EOF )                                                              # break
-    | RETURN expression SEMICOLON?                                                           # return
+    | RETURN expression ( SEMICOLON | EOF )                                                  # return
     | TRY block trap+                                                                        # try
-    | THROW expression SEMICOLON?                                                            # throw
+    | THROW expression ( SEMICOLON | EOF )                                                   # throw
-    | expression SEMICOLON?                                                                  # expr
+    | expression ( SEMICOLON | EOF )                                                         # expr
     ;
 
 block

modules/lang-painless/src/test/java/org/elasticsearch/painless/NoSemiColonTests.java

@@ -19,161 +19,60 @@
 
 package org.elasticsearch.painless;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
 public class NoSemiColonTests extends ScriptTestCase {
 
-    public void testIfStatement() {
-        assertEquals(1, exec("int x = 5 if (x == 5) return 1 return 0"));
-        assertEquals(0, exec("int x = 4 if (x == 5) return 1 else return 0"));
-        assertEquals(2, exec("int x = 4 if (x == 5) return 1 else if (x == 4) return 2 else return 0"));
-        assertEquals(1, exec("int x = 4 if (x == 5) return 1 else if (x == 4) return 1 else return 0"));
-
-        assertEquals(3, exec(
-                "int x = 5\n" +
-                        "if (x == 5) {\n" +
-                        "    int y = 2\n" +
-                        "    \n" +
-                        "    if (y == 2) {\n" +
-                        "        x = 3\n" +
-                        "    }\n" +
-                        "    \n" +
-                        "}\n" +
-                        "\n" +
-                        "return x\n"));
-    }
-
-    public void testWhileStatement() {
-
-        assertEquals("aaaaaa", exec("String c = \"a\" int x while (x < 5) { ++x c += \"a\" } return c"));
-
-        Object value = exec(
-                " byte[][] b = new byte[5][5]       \n" +
-                " byte x = 0, y                     \n" +
-                "                                   \n" +
-                " while (x < 5) {                   \n" +
-                "     y = 0                         \n" +
-                "                                   \n" +
-                "     while (y < 5) {               \n" +
-                "         b[x][y] = (byte)(x*y)     \n" +
-                "         ++y                       \n" +
-                "     }                             \n" +
-                "                                   \n" +
-                "     ++x                           \n" +
-                " }                                 \n" +
-                "                                   \n" +
-                " return b                          \n");
-
-        byte[][] b = (byte[][])value;
-
-        for (byte x = 0; x < 5; ++x) {
-            for (byte y = 0; y < 5; ++y) {
-                assertEquals(x*y, b[x][y]);
-            }
-        }
-    }
-
-    public void testDoWhileStatement() {
-        assertEquals("aaaaaa", exec("String c = \"a\" int x do { c += \"a\"; ++x } while (x < 5) return c"));
-
-        Object value = exec(
-                " long[][] l = new long[5][5]      \n" +
-                " long x = 0, y                    \n" +
-                "                                  \n" +
-                " do {                             \n" +
-                "     y = 0                        \n" +
-                "                                  \n" +
-                "     do {                         \n" +
-                "         l[(int)x][(int)y] = x*y; \n" +
-                "         ++y                      \n" +
-                "     } while (y < 5)              \n" +
-                "                                  \n" +
-                "     ++x                          \n" +
-                " } while (x < 5)                  \n" +
-                "                                  \n" +
-                " return l                         \n");
-
-        long[][] l = (long[][])value;
-
-        for (long x = 0; x < 5; ++x) {
-            for (long y = 0; y < 5; ++y) {
-                assertEquals(x*y, l[(int)x][(int)y]);
-            }
-        }
-    }
-
-    public void testForStatement() {
-        assertEquals("aaaaaa", exec("String c = \"a\" for (int x = 0; x < 5; ++x) c += \"a\" return c"));
-
-        Object value = exec(
-                " int[][] i = new int[5][5]         \n" +
-                " for (int x = 0; x < 5; ++x) {     \n" +
-                "     for (int y = 0; y < 5; ++y) { \n" +
-                "         i[x][y] = x*y             \n" +
-                "     }                             \n" +
-                " }                                 \n" +
-                "                                   \n" +
-                " return i                          \n");
-
-        int[][] i = (int[][])value;
-
-        for (int x = 0; x < 5; ++x) {
-            for (int y = 0; y < 5; ++y) {
-                assertEquals(x*y, i[x][y]);
-            }
-        }
-    }
-
     public void testDeclarationStatement() {
-        assertEquals((byte)2, exec("byte a = 2 return a"));
+        assertEquals((byte)2, exec("byte a = 2; return a"));
-        assertEquals((short)2, exec("short a = 2 return a"));
+        assertEquals((short)2, exec("short a = 2; return a"));
-        assertEquals((char)2, exec("char a = 2 return a"));
+        assertEquals((char)2, exec("char a = 2; return a"));
-        assertEquals(2, exec("int a = 2 return a"));
+        assertEquals(2, exec("int a = 2; return a"));
-        assertEquals(2L, exec("long a = 2 return a"));
+        assertEquals(2L, exec("long a = 2; return a"));
-        assertEquals(2F, exec("float a = 2 return a"));
+        assertEquals(2F, exec("float a = 2; return a"));
-        assertEquals(2.0, exec("double a = 2 return a"));
+        assertEquals(2.0, exec("double a = 2; return a"));
-        assertEquals(false, exec("boolean a = false return a"));
+        assertEquals(false, exec("boolean a = false; return a"));
-        assertEquals("string", exec("String a = \"string\" return a"));
+        assertEquals("string", exec("String a = \"string\"; return a"));
-        assertEquals(HashMap.class, exec("Map<String, Object> a = new HashMap<String, Object>() return a").getClass());
+        assertEquals(HashMap.class, exec("Map<String, Object> a = new HashMap<String, Object>(); return a").getClass());
 
-        assertEquals(byte[].class, exec("byte[] a = new byte[1] return a").getClass());
+        assertEquals(byte[].class, exec("byte[] a = new byte[1]; return a").getClass());
-        assertEquals(short[].class, exec("short[] a = new short[1] return a").getClass());
+        assertEquals(short[].class, exec("short[] a = new short[1]; return a").getClass());
-        assertEquals(char[].class, exec("char[] a = new char[1] return a").getClass());
+        assertEquals(char[].class, exec("char[] a = new char[1]; return a").getClass());
-        assertEquals(int[].class, exec("int[] a = new int[1] return a").getClass());
+        assertEquals(int[].class, exec("int[] a = new int[1]; return a").getClass());
-        assertEquals(long[].class, exec("long[] a = new long[1] return a").getClass());
+        assertEquals(long[].class, exec("long[] a = new long[1]; return a").getClass());
-        assertEquals(float[].class, exec("float[] a = new float[1] return a").getClass());
+        assertEquals(float[].class, exec("float[] a = new float[1]; return a").getClass());
-        assertEquals(double[].class, exec("double[] a = new double[1] return a").getClass());
+        assertEquals(double[].class, exec("double[] a = new double[1]; return a").getClass());
-        assertEquals(boolean[].class, exec("boolean[] a = new boolean[1] return a").getClass());
+        assertEquals(boolean[].class, exec("boolean[] a = new boolean[1]; return a").getClass());
-        assertEquals(String[].class, exec("String[] a = new String[1] return a").getClass());
+        assertEquals(String[].class, exec("String[] a = new String[1]; return a").getClass());
-        assertEquals(Map[].class, exec("Map<String,Object>[] a = new Map<String,Object>[1] return a").getClass());
+        assertEquals(Map[].class, exec("Map<String,Object>[] a = new Map<String,Object>[1]; return a").getClass());
 
-        assertEquals(byte[][].class, exec("byte[][] a = new byte[1][2] return a").getClass());
+        assertEquals(byte[][].class, exec("byte[][] a = new byte[1][2]; return a").getClass());
-        assertEquals(short[][][].class, exec("short[][][] a = new short[1][2][3] return a").getClass());
+        assertEquals(short[][][].class, exec("short[][][] a = new short[1][2][3]; return a").getClass());
-        assertEquals(char[][][][].class, exec("char[][][][] a = new char[1][2][3][4] return a").getClass());
+        assertEquals(char[][][][].class, exec("char[][][][] a = new char[1][2][3][4]; return a").getClass());
-        assertEquals(int[][][][][].class, exec("int[][][][][] a = new int[1][2][3][4][5] return a").getClass());
+        assertEquals(int[][][][][].class, exec("int[][][][][] a = new int[1][2][3][4][5]; return a").getClass());
-        assertEquals(long[][].class, exec("long[][] a = new long[1][2] return a").getClass());
+        assertEquals(long[][].class, exec("long[][] a = new long[1][2]; return a").getClass());
-        assertEquals(float[][][].class, exec("float[][][] a = new float[1][2][3] return a").getClass());
+        assertEquals(float[][][].class, exec("float[][][] a = new float[1][2][3]; return a").getClass());
-        assertEquals(double[][][][].class, exec("double[][][][] a = new double[1][2][3][4] return a").getClass());
+        assertEquals(double[][][][].class, exec("double[][][][] a = new double[1][2][3][4]; return a").getClass());
-        assertEquals(boolean[][][][][].class, exec("boolean[][][][][] a = new boolean[1][2][3][4][5] return a").getClass());
+        assertEquals(boolean[][][][][].class, exec("boolean[][][][][] a = new boolean[1][2][3][4][5]; return a").getClass());
-        assertEquals(String[][].class, exec("String[][] a = new String[1][2] return a").getClass());
+        assertEquals(String[][].class, exec("String[][] a = new String[1][2]; return a").getClass());
-        assertEquals(Map[][][].class, exec("Map<String,Object>[][][] a = new Map<String,Object>[1][2][3] return a").getClass());
+        assertEquals(Map[][][].class, exec("Map<String,Object>[][][] a = new Map<String,Object>[1][2][3]; return a").getClass());
     }
     
-    public void testContinueStatement() {
+    public void testExpression() {
-        assertEquals(9, exec("int x = 0, y = 0 while (x < 10) { ++x if (x == 1) continue ++y } return y"));
+        assertEquals(10, exec("10"));
-    }
+        assertEquals(10, exec("5 + 5"));
-
+        assertEquals(10, exec("5 + 5"));
-    public void testBreakStatement() {
+        assertEquals(10, exec("params.param == 'yes' ? 10 : 5", Collections.singletonMap("param", "yes")));
-        assertEquals(4, exec("int x = 0, y = 0 while (x < 10) { ++x if (x == 5) break ++y } return y"));
     }
 
     @SuppressWarnings("rawtypes")
     public void testReturnStatement() {
         assertEquals(10, exec("return 10"));
-        assertEquals(5, exec("int x = 5 return x"));
+        assertEquals(5, exec("int x = 5; return x"));
-        assertEquals(4, exec("int[] x = new int[2] x[1] = 4 return x[1]"));
+        assertEquals(4, exec("int[] x = new int[2]; x[1] = 4; return x[1]"));
-        assertEquals(5, ((short[])exec("short[] s = new short[3] s[1] = 5 return s"))[1]);
+        assertEquals(5, ((short[])exec("short[] s = new short[3]; s[1] = 5; return s"))[1]);
-        assertEquals(10, ((Map)exec("Map<String,Object> s = new HashMap< String,Object>() s.put(\"x\", 10) return s")).get("x"));
+        assertEquals(10, ((Map)exec("Map<String,Object> s = new HashMap< String,Object>(); s.put(\"x\", 10); return s")).get("x"));
     }
 }

modules/lang-painless/src/test/java/org/elasticsearch/painless/StringTests.java

@@ -19,6 +19,8 @@
 
 package org.elasticsearch.painless;
 
+import java.util.Locale;
+
 public class StringTests extends ScriptTestCase {
 
     public void testAppend() {
@@ -63,6 +65,21 @@ public class StringTests extends ScriptTestCase {
         assertEquals("cat" + "cat", exec("String s = 'cat'; return s + s;"));
     }
 
+    public void testAppendMultiple() {
+      assertEquals("cat" + true + "abc" + null, exec("String s = \"cat\"; return s + true + 'abc' + null;"));
+    }
+
+    public void testAppendMany() {
+      StringBuilder script = new StringBuilder("String s = \"cat\"; return s");
+      StringBuilder result = new StringBuilder("cat");
+      for (int i = 0; i < 200 /* indy limit */ + 10; i++) {
+        final String s = String.format(Locale.ROOT,  "%03d", i);
+        script.append(" + '").append(s).append("'.toString()");
+        result.append(s);
+      }
+      assertEquals(result.toString(), exec(script.toString()));
+    }
+
     public void testStringAPI() {
         assertEquals("", exec("return new String();"));
         assertEquals('x', exec("String s = \"x\"; return s.charAt(0);"));
@@ -127,8 +144,8 @@ public class StringTests extends ScriptTestCase {
         assertEquals("c", exec("return (String)(char)\"c\""));
         assertEquals("c", exec("return (String)(char)'c'"));
 
-        assertEquals('c', exec("String s = \"c\" (char)s"));
+        assertEquals('c', exec("String s = \"c\"; (char)s"));
-        assertEquals('c', exec("String s = 'c' (char)s"));
+        assertEquals('c', exec("String s = 'c'; (char)s"));
 
         try {
             assertEquals("cc", exec("return (String)(char)\"cc\""));
@@ -145,14 +162,14 @@ public class StringTests extends ScriptTestCase {
         }
 
         try {
-            assertEquals('c', exec("String s = \"cc\" (char)s"));
+            assertEquals('c', exec("String s = \"cc\"; (char)s"));
             fail();
         } catch (final ClassCastException cce) {
             assertTrue(cce.getMessage().contains("Cannot cast [String] with length greater than one to [char]."));
         }
 
         try {
-            assertEquals('c', exec("String s = 'cc' (char)s"));
+            assertEquals('c', exec("String s = 'cc'; (char)s"));
             fail();
         } catch (final ClassCastException cce) {
             assertTrue(cce.getMessage().contains("Cannot cast [String] with length greater than one to [char]."));
@@ -163,8 +180,8 @@ public class StringTests extends ScriptTestCase {
         assertEquals("c", exec("return (String)(Character)\"c\""));
         assertEquals("c", exec("return (String)(Character)'c'"));
 
-        assertEquals('c', exec("String s = \"c\" (Character)s"));
+        assertEquals('c', exec("String s = \"c\"; (Character)s"));
-        assertEquals('c', exec("String s = 'c' (Character)s"));
+        assertEquals('c', exec("String s = 'c'; (Character)s"));
 
         try {
             assertEquals("cc", exec("return (String)(Character)\"cc\""));
@@ -181,14 +198,14 @@ public class StringTests extends ScriptTestCase {
         }
 
         try {
-            assertEquals('c', exec("String s = \"cc\" (Character)s"));
+            assertEquals('c', exec("String s = \"cc\"; (Character)s"));
             fail();
         } catch (final ClassCastException cce) {
             assertTrue(cce.getMessage().contains("Cannot cast [String] with length greater than one to [Character]."));
         }
 
         try {
-            assertEquals('c', exec("String s = 'cc' (Character)s"));
+            assertEquals('c', exec("String s = 'cc'; (Character)s"));
             fail();
         } catch (final ClassCastException cce) {
             assertTrue(cce.getMessage().contains("Cannot cast [String] with length greater than one to [Character]."));

modules/lang-painless/src/test/java/org/elasticsearch/painless/WhenThingsGoWrongTests.java

@@ -90,7 +90,7 @@ public class WhenThingsGoWrongTests extends ScriptTestCase {
                    "The maximum number of statements that can be executed in a loop has been reached."));
 
         expected = expectThrows(PainlessError.class, () -> {
-            exec("while (true) {int y = 5}");
+            exec("while (true) {int y = 5;}");
         });
         assertTrue(expected.getMessage().contains(
                    "The maximum number of statements that can be executed in a loop has been reached."));
@@ -116,7 +116,7 @@ public class WhenThingsGoWrongTests extends ScriptTestCase {
                    "The maximum number of statements that can be executed in a loop has been reached."));
 
         expected = expectThrows(PainlessError.class, () -> {
-            exec("for (;;) {int x = 5}");
+            exec("for (;;) {int x = 5;}");
             fail("should have hit PainlessError");
         });
         assertTrue(expected.getMessage().contains(
@@ -130,7 +130,7 @@ public class WhenThingsGoWrongTests extends ScriptTestCase {
                    "The maximum number of statements that can be executed in a loop has been reached."));
 
         RuntimeException parseException = expectThrows(RuntimeException.class, () -> {
-            exec("try { int x } catch (PainlessError error) {}");
+            exec("try { int x; } catch (PainlessError error) {}");
             fail("should have hit ParseException");
         });
         assertTrue(parseException.getMessage().contains("Not a type [PainlessError]."));