Update: support logical assignments in code path analysis (refs #13569)

lib/linter/code-path-analysis/code-path-analyzer.js

@@ -39,6 +39,17 @@ function isHandledLogicalOperator(operator) {
     return operator === "&&" || operator === "||" || operator === "??";
 }
 
+/**
+ * Checks whether the given assignment operator is a logical assignment operator.
+ * Logical assignments are taken into account for the code path analysis
+ * because of their short-circuiting semantics.
+ * @param {string} operator The operator found in the AssignmentExpression node
+ * @returns {boolean} `true` if the operator is "&&=" or "||=" or "??="
+ */
+function isLogicalAssignmentOperator(operator) {
+    return operator === "&&=" || operator === "||=" || operator === "??=";
+}
+
 /**
  * Gets the label if the parent node of a given node is a LabeledStatement.
  * @param {ASTNode} node A node to get.
@@ -71,6 +82,9 @@ function isForkingByTrueOrFalse(node) {
         case "LogicalExpression":
             return isHandledLogicalOperator(parent.operator);
 
+        case "AssignmentExpression":
+            return isLogicalAssignmentOperator(parent.operator);
+
         default:
             return false;
     }
@@ -266,6 +280,15 @@ function preprocess(analyzer, node) {
             }
             break;
 
+        case "AssignmentExpression":
+            if (
+                parent.right === node &&
+                isLogicalAssignmentOperator(parent.operator)
+            ) {
+                state.makeLogicalRight();
+            }
+            break;
+
         case "ConditionalExpression":
         case "IfStatement":
 
@@ -413,6 +436,15 @@ function processCodePathToEnter(analyzer, node) {
             }
             break;
 
+        case "AssignmentExpression":
+            if (isLogicalAssignmentOperator(node.operator)) {
+                state.pushChoiceContext(
+                    node.operator.slice(0, -1), // removes `=` from the end
+                    isForkingByTrueOrFalse(node)
+                );
+            }
+            break;
+
         case "ConditionalExpression":
         case "IfStatement":
             state.pushChoiceContext("test", false);
@@ -491,6 +523,12 @@ function processCodePathToExit(analyzer, node) {
             }
             break;
 
+        case "AssignmentExpression":
+            if (isLogicalAssignmentOperator(node.operator)) {
+                state.popChoiceContext();
+            }
+            break;
+
         case "SwitchStatement":
             state.popSwitchContext();
             break;

lib/linter/code-path-analysis/code-path-state.js

@@ -317,7 +317,7 @@ class CodePathState {
     //--------------------------------------------------------------------------
 
     /**
-     * Creates a context for ConditionalExpression, LogicalExpression,
+     * Creates a context for ConditionalExpression, LogicalExpression, AssignmentExpression (logical assignments only),
      * IfStatement, WhileStatement, DoWhileStatement, or ForStatement.
      *
      * LogicalExpressions have cases that it goes different paths between the
@@ -339,7 +339,7 @@ class CodePathState {
      *     a -> b -> foo();
      *     a -> b -> bar();
      * @param {string} kind A kind string.
-     *   If the new context is LogicalExpression's, this is `"&&"` or `"||"`.
+     *   If the new context is LogicalExpression's or AssignmentExpression's, this is `"&&"` or `"||"` or `"??"`.
      *   If it's IfStatement's or ConditionalExpression's, this is `"test"`.
      *   Otherwise, this is `"loop"`.
      * @param {boolean} isForkingAsResult A flag that shows that goes different

tests/fixtures/code-path-analysis/assignment--do-while-and.js

@@ -0,0 +1,21 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_2->s1_4;
+s1_3->s1_4->final;
+*/
+do {
+    foo();
+} while (a &&= b);
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nDoWhileStatement:enter"];
+    s1_2[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="DoWhileStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_2->s1_4;
+    s1_3->s1_4->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--do-while-or.js

@@ -0,0 +1,21 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_2->s1_2;
+s1_3->s1_4->final;
+*/
+do {
+    foo();
+} while (a ||= b);
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nDoWhileStatement:enter"];
+    s1_2[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="DoWhileStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_2->s1_2;
+    s1_3->s1_4->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--do-while-qq.js

@@ -0,0 +1,23 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_2->s1_2;
+s1_3->s1_4;
+s1_2->s1_4->final;
+*/
+do {
+    foo();
+} while (a ??= b);
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nDoWhileStatement:enter"];
+    s1_2[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="DoWhileStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_2->s1_2;
+    s1_3->s1_4;
+    s1_2->s1_4->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-and-1.js

@@ -0,0 +1,23 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_6;
+s1_3->s1_6->final;
+*/
+for (init; a &&= b; update) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="Identifier (update)"];
+    s1_6[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_6;
+    s1_3->s1_6->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-and-2.js

@@ -0,0 +1,22 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_5;
+s1_3->s1_5->final;
+*/
+for (init; a &&= b;) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_5;
+    s1_3->s1_5->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-or-1.js

@@ -0,0 +1,23 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_4;
+s1_3->s1_6->final;
+*/
+for (init; a ||= b; update) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="Identifier (update)"];
+    s1_6[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_4;
+    s1_3->s1_6->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-or-2.js

@@ -0,0 +1,22 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_4;
+s1_3->s1_5->final;
+*/
+for (init; a ||= b;) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_4;
+    s1_3->s1_5->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-qq-1.js

@@ -0,0 +1,25 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_4;
+s1_3->s1_6;
+s1_2->s1_6->final;
+*/
+for (init; a ??= b; update) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="Identifier (update)"];
+    s1_6[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_2->s1_4;
+    s1_3->s1_6;
+    s1_2->s1_6->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--for-qq-2.js

@@ -0,0 +1,24 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_4;
+s1_3->s1_5;
+s1_2->s1_5->final;
+*/
+for (init; a ??= b;) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nForStatement:enter\nIdentifier (init)"];
+    s1_2[label="AssignmentExpression:enter\nIdentifier (a)"];
+    s1_3[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="ForStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_2->s1_4;
+    s1_3->s1_5;
+    s1_2->s1_5->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--if-and-1.js

@@ -0,0 +1,23 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4;
+s1_1->s1_4;
+s1_2->s1_4->final;
+*/
+if (a &&= b) {
+    foo();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nIfStatement:enter\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_2[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_3[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_4[label="IfStatement:exit\nProgram:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4;
+    s1_1->s1_4;
+    s1_2->s1_4->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--if-and-2.js

@@ -0,0 +1,28 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_5;
+s1_1->s1_4->s1_5;
+s1_2->s1_4;
+s1_5->final;
+*/
+if (a &&= b) {
+    foo();
+} else {
+    bar();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nIfStatement:enter\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_2[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_3[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (foo)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_5[label="IfStatement:exit\nProgram:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (bar)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    initial->s1_1->s1_2->s1_3->s1_5;
+    s1_1->s1_4->s1_5;
+    s1_2->s1_4;
+    s1_5->final;
+}
+*/

tests/fixtures/code-path-analysis/assignment--if-and-3.js

@@ -0,0 +1,36 @@
+/*expected
+initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_7->s1_9;
+s1_1->s1_8->s1_9;
+s1_2->s1_8;
+s1_3->s1_8;
+s1_4->s1_6->s1_7;
+s1_9->final;
+*/
+if ((a &&= b) && c) {
+    d ? foo() : bar();
+} else {
+    baz();
+}
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nIfStatement:enter\nLogicalExpression:enter\nAssignmentExpression:enter\nIdentifier (a)"];
+    s1_2[label="Identifier (b)\nAssignmentExpression:exit"];
+    s1_3[label="Identifier (c)\nLogicalExpression:exit"];
+    s1_4[label="BlockStatement:enter\nExpressionStatement:enter\nConditionalExpression:enter\nIdentifier (d)"];
+    s1_5[label="CallExpression:enter\nIdentifier (foo)\nCallExpression:exit"];
+    s1_7[label="ConditionalExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_9[label="IfStatement:exit\nProgram:exit"];
+    s1_8[label="BlockStatement:enter\nExpressionStatement:enter\nCallExpression:enter\nIdentifier (baz)\nCallExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s1_6[label="CallExpression:enter\nIdentifier (bar)\nCallExpression:exit"];
+    initial->s1_1->s1_2->s1_3->s1_4->s1_5->s1_7->s1_9;
+    s1_1->s1_8->s1_9;
+    s1_2->s1_8;
+    s1_3->s1_8;
+    s1_4->s1_6->s1_7;
+    s1_9->final;
+}
+*/