fix(node): Record local variables with falsy values, null and undefined (#10821)

We previously didn't record local local variables with falsy values
because we checked for truthiness instead of definedness when unrolling
and serializing the variable values. This PR changes how we check for
and extract variable properties to record

- falsy values (`0`, `''`, `false`)
- `null`
- `undefined`
---------

Co-authored-by: Luca Forstner <[email protected]>

Author: Lms24

dev-packages/node-integration-tests/suites/public-api/LocalVariables/local-variables-caught.js

@@ -20,6 +20,11 @@ function one(name) {
     name,
     num: 5,
   };
+  const bool = false;
+  const num = 0;
+  const str = '';
+  const something = undefined;
+  const somethingElse = null;
 
   const ty = new Some();
 

dev-packages/node-integration-tests/suites/public-api/LocalVariables/local-variables-caught.mjs

@@ -22,6 +22,11 @@ function one(name) {
     functionsShouldNotBeIncluded: () => {},
     functionsShouldNotBeIncluded2() {},
   };
+  const bool = false;
+  const num = 0;
+  const str = '';
+  const something = undefined;
+  const somethingElse = null;
 
   const ty = new Some();
 

dev-packages/node-integration-tests/suites/public-api/LocalVariables/local-variables-memory-test.js

@@ -22,6 +22,11 @@ function one(name) {
     name,
     num: 5,
   };
+  const bool = false;
+  const num = 0;
+  const str = '';
+  const something = undefined;
+  const somethingElse = null;
 
   const ty = new Some();
 

dev-packages/node-integration-tests/suites/public-api/LocalVariables/local-variables.js

@@ -24,6 +24,11 @@ function one(name) {
     name,
     num: 5,
   };
+  const bool = false;
+  const num = 0;
+  const str = '';
+  const something = undefined;
+  const somethingElse = null;
 
   const ty = new Some();
 

dev-packages/node-integration-tests/suites/public-api/LocalVariables/no-local-variables.js

@@ -23,6 +23,11 @@ function one(name) {
     name,
     num: 5,
   };
+  const bool = false;
+  const num = 0;
+  const str = '';
+  const something = undefined;
+  const somethingElse = null;
 
   const ty = new Some();
 

dev-packages/node-integration-tests/suites/public-api/LocalVariables/test.ts

@@ -16,6 +16,11 @@ const EXPECTED_LOCAL_VARIABLES_EVENT = {
                 arr: [1, '2', null],
                 obj: { name: 'some name', num: 5 },
                 ty: '<Some>',
+                bool: false,
+                num: 0,
+                str: '',
+                something: '<undefined>',
+                somethingElse: '<null>',
               },
             }),
             expect.objectContaining({

packages/node-experimental/src/integrations/local-variables/local-variables-async.ts

@@ -42,10 +42,20 @@ async function unrollObject(session: Session, objectId: string, name: string, va
 }
 
 function unrollOther(prop: Runtime.PropertyDescriptor, vars: Variables): void {
-  if (prop?.value?.value) {
-    vars[prop.name] = prop.value.value;
-  } else if (prop?.value?.description && prop?.value?.type !== 'function') {
+  if (!prop.value) {
+    return;
+  }
+
+  if ('value' in prop.value) {
+    if (prop.value.value === undefined || prop.value.value === null) {
+      vars[prop.name] = `<${prop.value.value}>`;
+    } else {
+      vars[prop.name] = prop.value.value;
+    }
+  } else if ('description' in prop.value && prop.value.type !== 'function') {
     vars[prop.name] = `<${prop.value.description}>`;
+  } else if (prop.value.type === 'undefined') {
+    vars[prop.name] = '<undefined>';
   }
 }
 
@@ -63,7 +73,7 @@ async function getLocalVariables(session: Session, objectId: string): Promise<Va
     } else if (prop?.value?.objectId && prop?.value?.className === 'Object') {
       const id = prop.value.objectId;
       await unrollObject(session, id, prop.name, variables);
-    } else if (prop?.value?.value || prop?.value?.description) {
+    } else if (prop?.value) {
       unrollOther(prop, variables);
     }
   }

packages/node-experimental/src/integrations/local-variables/local-variables-sync.ts

@@ -128,7 +128,7 @@ class AsyncSession implements DebugSession {
         } else if (prop?.value?.objectId && prop?.value?.className === 'Object') {
           const id = prop.value.objectId;
           add(vars => this._unrollObject(id, prop.name, vars, next));
-        } else if (prop?.value?.value || prop?.value?.description) {
+        } else if (prop?.value) {
           add(vars => this._unrollOther(prop, vars, next));
         }
       }
@@ -191,10 +191,18 @@ class AsyncSession implements DebugSession {
    * Unrolls other properties
    */
   private _unrollOther(prop: Runtime.PropertyDescriptor, vars: Variables, next: (vars: Variables) => void): void {
-    if (prop?.value?.value) {
-      vars[prop.name] = prop.value.value;
-    } else if (prop?.value?.description && prop?.value?.type !== 'function') {
-      vars[prop.name] = `<${prop.value.description}>`;
+    if (prop.value) {
+      if ('value' in prop.value) {
+        if (prop.value.value === undefined || prop.value.value === null) {
+          vars[prop.name] = `<${prop.value.value}>`;
+        } else {
+          vars[prop.name] = prop.value.value;
+        }
+      } else if ('description' in prop.value && prop.value.type !== 'function') {
+        vars[prop.name] = `<${prop.value.description}>`;
+      } else if (prop.value.type === 'undefined') {
+        vars[prop.name] = '<undefined>';
+      }
     }
 
     next(vars);

packages/node/src/integrations/local-variables/local-variables-async.ts

@@ -42,10 +42,20 @@ async function unrollObject(session: Session, objectId: string, name: string, va
 }
 
 function unrollOther(prop: Runtime.PropertyDescriptor, vars: Variables): void {
-  if (prop?.value?.value) {
-    vars[prop.name] = prop.value.value;
-  } else if (prop?.value?.description && prop?.value?.type !== 'function') {
+  if (!prop.value) {
+    return;
+  }
+
+  if ('value' in prop.value) {
+    if (prop.value.value === undefined || prop.value.value === null) {
+      vars[prop.name] = `<${prop.value.value}>`;
+    } else {
+      vars[prop.name] = prop.value.value;
+    }
+  } else if ('description' in prop.value && prop.value.type !== 'function') {
     vars[prop.name] = `<${prop.value.description}>`;
+  } else if (prop.value.type === 'undefined') {
+    vars[prop.name] = '<undefined>';
   }
 }
 
@@ -63,7 +73,7 @@ async function getLocalVariables(session: Session, objectId: string): Promise<Va
     } else if (prop?.value?.objectId && prop?.value?.className === 'Object') {
       const id = prop.value.objectId;
       await unrollObject(session, id, prop.name, variables);
-    } else if (prop?.value?.value || prop?.value?.description) {
+    } else if (prop?.value) {
       unrollOther(prop, variables);
     }
   }

packages/node/src/integrations/local-variables/local-variables-sync.ts

@@ -129,7 +129,7 @@ class AsyncSession implements DebugSession {
         } else if (prop?.value?.objectId && prop?.value?.className === 'Object') {
           const id = prop.value.objectId;
           add(vars => this._unrollObject(id, prop.name, vars, next));
-        } else if (prop?.value?.value || prop?.value?.description) {
+        } else if (prop?.value) {
           add(vars => this._unrollOther(prop, vars, next));
         }
       }
@@ -192,10 +192,18 @@ class AsyncSession implements DebugSession {
    * Unrolls other properties
    */
   private _unrollOther(prop: Runtime.PropertyDescriptor, vars: Variables, next: (vars: Variables) => void): void {
-    if (prop?.value?.value) {
-      vars[prop.name] = prop.value.value;
-    } else if (prop?.value?.description && prop?.value?.type !== 'function') {
-      vars[prop.name] = `<${prop.value.description}>`;
+    if (prop.value) {
+      if ('value' in prop.value) {
+        if (prop.value.value === undefined || prop.value.value === null) {
+          vars[prop.name] = `<${prop.value.value}>`;
+        } else {
+          vars[prop.name] = prop.value.value;
+        }
+      } else if ('description' in prop.value && prop.value.type !== 'function') {
+        vars[prop.name] = `<${prop.value.description}>`;
+      } else if (prop.value.type === 'undefined') {
+        vars[prop.name] = '<undefined>';
+      }
     }
 
     next(vars);