fix: branch distance calculation (#170)

Author: dstallenberg

libraries/search-javascript/lib/criterion/BranchDistanceVisitor.ts

@@ -126,9 +126,6 @@ export class BranchDistanceVisitor extends AbstractSyntaxTreeVisitor {
 
       if (property.isIdentifier()) {
         const objectValue = this._valueMap.get(object.toString());
-        const argument = path.get("arguments")[0];
-        argument.visit();
-        const argumentValue = <string>this._valueMap.get(argument.toString());
 
         // TODO should check if the value is actually a string
         if (typeof objectValue !== "string") {
@@ -137,6 +134,12 @@ export class BranchDistanceVisitor extends AbstractSyntaxTreeVisitor {
 
         switch (property.node.name) {
           case "endsWith": {
+            const argument = path.get("arguments")[0];
+            argument.visit();
+            const argumentValue = <string>(
+              this._valueMap.get(argument.toString())
+            );
+            
             const endOfObject =
               objectValue.length > argumentValue.length
                 ? objectValue.slice(-argumentValue.length)
@@ -166,6 +169,12 @@ export class BranchDistanceVisitor extends AbstractSyntaxTreeVisitor {
             break;
           }
           case "startsWith": {
+            const argument = path.get("arguments")[0];
+            argument.visit();
+            const argumentValue = <string>(
+              this._valueMap.get(argument.toString())
+            );
+
             const startOfObject =
               objectValue.length > argumentValue.length
                 ? objectValue.slice(0, argumentValue.length)
@@ -195,6 +204,12 @@ export class BranchDistanceVisitor extends AbstractSyntaxTreeVisitor {
             break;
           }
           case "includes": {
+            const argument = path.get("arguments")[0];
+            argument.visit();
+            const argumentValue = <string>(
+              this._valueMap.get(argument.toString())
+            );
+
             this._isDistanceMap.set(path.toString(), true);
 
             if (this._inverted) {