SONARPY-915 Match / case statement: support mapping patterns

Author: guillaume-dequenne

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/BaseTreeVisitor.java

@@ -83,6 +83,11 @@ public void visitDelStatement(DelStatement pyDelStatementTree) {
     scan(pyDelStatementTree.expressions());
   }
 
+  @Override
+  public void visitDoubleStarPattern(DoubleStarPattern doubleStarPattern) {
+    scan(doubleStarPattern.capturePattern());
+  }
+
   @Override
   public void visitPassStatement(PassStatement pyPassStatementTree) {
     // nothing to visit for pass statement
@@ -417,6 +422,12 @@ public void visitKeyValuePair(KeyValuePair keyValuePair) {
     scan(keyValuePair.value());
   }
 
+  @Override
+  public void visitKeyValuePattern(KeyValuePattern keyValuePattern) {
+    scan(keyValuePattern.key());
+    scan(keyValuePattern.value());
+  }
+
   @Override
   public void visitDictCompExpression(DictCompExpressionImpl tree) {
     scan(tree.keyExpression());
@@ -501,6 +512,10 @@ public void visitOrPattern(OrPattern orPattern) {
     scan(orPattern.patterns());
   }
 
+  public void visitMappingPattern(MappingPattern mappingPattern) {
+    scan(mappingPattern.elements());
+  }
+
   @Override
   public void visitGuard(Guard guard) {
     scan(guard.condition());

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/DoubleStarPattern.java

@@ -0,0 +1,37 @@
+/*
+ * SonarQube Python Plugin
+ * Copyright (C) 2011-2021 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.plugins.python.api.tree;
+
+/**
+ * Double Star Pattern (only used within mapping patterns)
+ *
+ * <pre>
+ *   case {"x": "foo", **rest}:
+ *     ...
+ * </pre>
+ *
+ * See https://docs.python.org/3/reference/compound_stmts.html#mapping-patterns
+ */
+public interface DoubleStarPattern extends Pattern {
+
+  Token doubleStarToken();
+
+  CapturePattern capturePattern();
+}

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/KeyValuePattern.java

@@ -0,0 +1,38 @@
+/*
+ * SonarQube Python Plugin
+ * Copyright (C) 2011-2021 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.plugins.python.api.tree;
+
+/**
+ * Key Value Pattern (only used within mapping patterns)
+ *
+ * <pre>
+ *   case {"key": "value"}:
+ *     ...
+ * </pre>
+ *
+ * See https://docs.python.org/3/reference/compound_stmts.html#mapping-patterns
+ */
+public interface KeyValuePattern extends Pattern {
+  Pattern key();
+
+  Token colon();
+
+  Pattern value();
+}

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/MappingPattern.java

@@ -0,0 +1,43 @@
+/*
+ * SonarQube Python Plugin
+ * Copyright (C) 2011-2021 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.plugins.python.api.tree;
+
+import java.util.List;
+
+/**
+ * Mapping Pattern
+ *
+ * <pre>
+ *   case {"x": "foo", "y": "bar"}:
+ *     ...
+ * </pre>
+ *
+ * See https://docs.python.org/3/reference/compound_stmts.html#mapping-patterns
+ */
+public interface MappingPattern extends Pattern {
+
+  Token lCurlyBrace();
+
+  List<Pattern> elements();
+
+  List<Token> commas();
+
+  Token rCurlyBrace();
+}

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/Tree.java

@@ -80,6 +80,8 @@ enum Kind {
 
     DOTTED_NAME(DottedName.class),
 
+    DOUBLE_STAR_PATTERN(DoubleStarPattern.class),
+
     ELLIPSIS(EllipsisExpression.class),
 
     ELSE_CLAUSE(ElseClause.class),
@@ -124,6 +126,8 @@ enum Kind {
 
     MATCH_STMT(MatchStatement.class),
 
+    MAPPING_PATTERN(MappingPattern.class),
+
     NAME(Name.class),
 
     NONLOCAL_STMT(NonlocalStatement.class),
@@ -233,6 +237,7 @@ enum Kind {
     ASSIGNMENT_EXPRESSION(AssignmentExpression.class),
 
     KEY_VALUE_PAIR(KeyValuePair.class),
+    KEY_VALUE_PATTERN(KeyValuePattern.class),
     TOKEN(Token.class);
     final Class<? extends Tree> associatedInterface;
 

python-frontend/src/main/java/org/sonar/plugins/python/api/tree/TreeVisitor.java

@@ -37,6 +37,8 @@ public interface TreeVisitor {
 
   void visitDelStatement(DelStatement delStatement);
 
+  void visitDoubleStarPattern(DoubleStarPattern doubleStarPattern);
+
   void visitPassStatement(PassStatement passStatement);
 
   void visitPrintStatement(PrintStatement printStatement);
@@ -153,6 +155,8 @@ public interface TreeVisitor {
 
   void visitKeyValuePair(KeyValuePair keyValuePair);
 
+  void visitKeyValuePattern(KeyValuePattern keyValuePattern);
+
   void visitDictCompExpression(DictCompExpressionImpl dictCompExpression);
 
   void visitCompoundAssignment(CompoundAssignmentStatement compoundAssignmentStatement);
@@ -183,6 +187,8 @@ public interface TreeVisitor {
 
   void visitOrPattern(OrPattern orPattern);
 
+  void visitMappingPattern(MappingPattern mappingPattern);
+
   void visitGuard(Guard guard);
 
   void visitCapturePattern(CapturePattern capturePattern);

python-frontend/src/main/java/org/sonar/python/api/PythonGrammar.java

@@ -174,6 +174,10 @@ public enum PythonGrammar implements GrammarRuleKey {
   KEYWORD_PATTERN,
   NAME_OR_ATTR,
   VALUE_PATTERN,
+  MAPPING_PATTERN,
+  ITEMS_PATTERN,
+  KEY_VALUE_PATTERN,
+  DOUBLE_STAR_PATTERN,
 
   SIGNED_NUMBER,
   COMPLEX_NUMBER,
@@ -476,11 +480,20 @@ public static void compoundStatements(LexerfulGrammarBuilder b) {
 
     b.rule(PATTERNS).is(b.firstOf(OPEN_SEQUENCE_PATTERN, PATTERN));
     b.rule(PATTERN).is(b.firstOf(AS_PATTERN, OR_PATTERN));
-    b.rule(CLOSED_PATTERN).is(b.firstOf(CLASS_PATTERN, LITERAL_PATTERN, GROUP_PATTERN, WILDCARD_PATTERN, VALUE_PATTERN, CAPTURE_PATTERN, SEQUENCE_PATTERN));
+    b.rule(CLOSED_PATTERN).is(b.firstOf(CLASS_PATTERN, LITERAL_PATTERN, GROUP_PATTERN, WILDCARD_PATTERN, VALUE_PATTERN, CAPTURE_PATTERN, SEQUENCE_PATTERN, MAPPING_PATTERN));
     b.rule(AS_PATTERN).is(OR_PATTERN, "as", CAPTURE_PATTERN);
     b.rule(OR_PATTERN).is(CLOSED_PATTERN, b.zeroOrMore("|", CLOSED_PATTERN));
     b.rule(CAPTURE_PATTERN).is(NAME);
     b.rule(VALUE_PATTERN).is(ATTR);
+    b.rule(MAPPING_PATTERN).is(b.firstOf(
+      b.sequence("{", "}"),
+      b.sequence("{", DOUBLE_STAR_PATTERN, b.optional(","), "}"),
+      b.sequence("{", ITEMS_PATTERN, ",", DOUBLE_STAR_PATTERN, b.optional(","), "}"),
+      b.sequence("{", ITEMS_PATTERN, b.optional(","), "}")
+    ));
+    b.rule(ITEMS_PATTERN).is(KEY_VALUE_PATTERN, b.zeroOrMore(",", KEY_VALUE_PATTERN));
+    b.rule(KEY_VALUE_PATTERN).is(b.firstOf(LITERAL_PATTERN, VALUE_PATTERN), ":", PATTERN);
+    b.rule(DOUBLE_STAR_PATTERN).is("**", CAPTURE_PATTERN);
 
     b.rule(SEQUENCE_PATTERN).is(b.firstOf(
       b.sequence("[", b.optional(MAYBE_SEQUENCE_PATTERN) , "]"),
@@ -493,6 +506,7 @@ public static void compoundStatements(LexerfulGrammarBuilder b) {
 
     b.rule(CLASS_PATTERN).is(NAME_OR_ATTR, "(", b.optional(PATTERN_ARGS), ")");
     b.rule(NAME_OR_ATTR).is(NAME, b.zeroOrMore(".", NAME));
+    b.rule(ATTR).is(NAME, b.oneOrMore(".", NAME));
     b.rule(PATTERN_ARGS).is(PATTERN_ARG, b.zeroOrMore(b.sequence(",", PATTERN_ARG)), b.optional(","));
     b.rule(PATTERN_ARG).is(b.firstOf(KEYWORD_PATTERN, PATTERN));
     b.rule(KEYWORD_PATTERN).is(NAME, "=", PATTERN);
@@ -526,7 +540,6 @@ public static void compoundStatements(LexerfulGrammarBuilder b) {
     b.rule(DECORATORS).is(b.oneOrMore(DECORATOR));
     b.rule(DECORATOR).is("@", EXPR, NEWLINE);
     b.rule(DOTTED_NAME).is(NAME, b.zeroOrMore(".", NAME));
-    b.rule(ATTR).is(NAME, b.oneOrMore(b.nextNot("(", "["), TRAILER));
 
     b.rule(CLASSDEF).is(b.optional(DECORATORS), "class", CLASSNAME, b.optional("(", b.optional(ARGLIST), ")"), ":", SUITE);
     b.rule(CLASSNAME).is(NAME);

python-frontend/src/main/java/org/sonar/python/tree/DoubleStarPatternImpl.java

@@ -0,0 +1,63 @@
+/*
+ * SonarQube Python Plugin
+ * Copyright (C) 2011-2021 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.python.tree;
+
+import java.util.Arrays;
+import java.util.List;
+import org.sonar.plugins.python.api.tree.CapturePattern;
+import org.sonar.plugins.python.api.tree.DoubleStarPattern;
+import org.sonar.plugins.python.api.tree.Token;
+import org.sonar.plugins.python.api.tree.Tree;
+import org.sonar.plugins.python.api.tree.TreeVisitor;
+
+public class DoubleStarPatternImpl extends PyTree implements DoubleStarPattern {
+
+  private final Token doubleStarToken;
+  private final CapturePattern capturePattern;
+
+  public DoubleStarPatternImpl(Token doubleStarToken, CapturePattern capturePattern) {
+    this.doubleStarToken = doubleStarToken;
+    this.capturePattern = capturePattern;
+  }
+  @Override
+  public Token doubleStarToken() {
+    return doubleStarToken;
+  }
+
+  @Override
+  public CapturePattern capturePattern() {
+    return capturePattern;
+  }
+
+  @Override
+  public void accept(TreeVisitor visitor) {
+    visitor.visitDoubleStarPattern(this);
+  }
+
+  @Override
+  public Kind getKind() {
+    return Kind.DOUBLE_STAR_PATTERN;
+  }
+
+  @Override
+  List<Tree> computeChildren() {
+    return Arrays.asList(doubleStarToken, capturePattern);
+  }
+}

python-frontend/src/main/java/org/sonar/python/tree/KeyValuePairImpl.java

@@ -19,9 +19,8 @@
  */
 package org.sonar.python.tree;
 
+import java.util.Arrays;
 import java.util.List;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
 import javax.annotation.CheckForNull;
 import org.sonar.plugins.python.api.tree.Expression;
 import org.sonar.plugins.python.api.tree.KeyValuePair;
@@ -65,7 +64,7 @@ public void accept(TreeVisitor visitor) {
 
   @Override
   public List<Tree> computeChildren() {
-    return Stream.of(key, colon, value).collect(Collectors.toList());
+    return Arrays.asList(key, colon, value);
   }
 
   @Override