Fix signature help crash on malformed function declarations

src/Program.spec.ts

@@ -3200,6 +3200,54 @@ describe('Program', () => {
                 expect(signatureHelp[0].index, `failed on col ${col}`).to.equal(0);
             }
         });
+
+        it('does not crash on malformed function declaration with trailing comma', () => {
+            program.setFile('source/main.bs', `
+                sub test(p1 = invalid,
+                    result = 1
+                end sub
+            `);
+            program.validate();
+
+            // Try to get signature help at the position after the comma
+            // This should not crash even though the function declaration is malformed
+            const signatureHelp = program.getSignatureHelp(`${rootDir}/source/main.bs`, Position.create(1, 34));
+
+            // We don't necessarily expect specific results, just that it doesn't crash
+            expect(signatureHelp).to.be.an('array');
+        });
+
+        it('does not crash on incomplete function call', () => {
+            program.setFile('source/main.bs', `
+                function main()
+                    someFunction(
+                end function
+                function someFunction(param1 as string)
+                end function
+            `);
+            program.validate();
+
+            // Try to get signature help after the opening parenthesis
+            const signatureHelp = program.getSignatureHelp(`${rootDir}/source/main.bs`, Position.create(2, 32));
+
+            // We don't necessarily expect specific results, just that it doesn't crash
+            expect(signatureHelp).to.be.an('array');
+        });
+
+        it('does not crash on malformed function declaration with missing closing paren', () => {
+            program.setFile('source/main.bs', `
+                sub test(p1 = invalid
+                    result = 1
+                end sub
+            `);
+            program.validate();
+
+            // Try to get signature help at the position where closing paren should be
+            const signatureHelp = program.getSignatureHelp(`${rootDir}/source/main.bs`, Position.create(1, 33));
+
+            // We don't necessarily expect specific results, just that it doesn't crash
+            expect(signatureHelp).to.be.an('array');
+        });
     });
 
     describe('plugins', () => {

src/bscPlugin/CallExpressionInfo.ts

@@ -93,6 +93,9 @@ export class CallExpressionInfo {
     }
 
     isPositionBetweenParentheses() {
+        if (!this.callExpression) {
+            return false;
+        }
         let boundingRange = util.createBoundingRange(this.callExpression.openingParen, this.callExpression.closingParen);
         return util.rangeContains(boundingRange, this.position);
     }
@@ -106,8 +109,8 @@ export class CallExpressionInfo {
         let callExpression = expression?.findAncestor<CallExpression | CallfuncExpression>(isCallFuncOrCallExpression);
         if (callExpression && callExpression.callee === expression) {
             //this expression is the NAME of a CallExpression
-            callExpression = expression.parent.findAncestor<CallExpression | CallfuncExpression>(isCallFuncOrCallExpression);
-        } else if (isDottedGetExpression(expression.parent) && expression?.parent?.parent === callExpression) {
+            callExpression = expression.parent?.findAncestor<CallExpression | CallfuncExpression>(isCallFuncOrCallExpression);
+        } else if (isDottedGetExpression(expression?.parent) && expression?.parent?.parent === callExpression) {
             callExpression = callExpression.findAncestor<CallExpression | CallfuncExpression>(isCallFuncOrCallExpression);
         }
 
@@ -151,6 +154,9 @@ export class CallExpressionInfo {
     }
 
     private getParameterIndex() {
+        if (!this.callExpression || !this.callExpression.args) {
+            return 0;
+        }
         for (let i = this.callExpression.args.length - 1; i > -1; i--) {
             let argExpression = this.callExpression.args[i];
             let comparison = util.comparePositionToRange(this.position, argExpression.range);
@@ -160,7 +166,6 @@ export class CallExpressionInfo {
         }
 
         return 0;
-
     }
 
 }

src/lsp/ProjectManager.ts

@@ -497,11 +497,11 @@ export class ProjectManager {
 
         //if the request has been cancelled since originally requested due to idle time being slow, skip the rest of the wor
         if (options?.cancellationToken?.isCancellationRequested) {
-            this.logger.log('ProjectManager getCompletions cancelled', options);
+            this.logger.debug('ProjectManager getCompletions cancelled', options);
             return;
         }
 
-        this.logger.log('ProjectManager getCompletions', options);
+        this.logger.debug('ProjectManager getCompletions', options);
         //Ask every project for results, keep whichever one responds first that has a valid response
         let result = await util.promiseRaceMatch(
             this.projects.map(x => x.getCompletions(options)),