Correctly replaces string when selecting in dropdown

app/assets/javascripts/filtered_search/dropdown_utils.js.es6

@@ -76,13 +76,25 @@
     static getSearchInput(filteredSearchInput) {
       const selectionStart = filteredSearchInput.selectionStart;
       const inputValue = filteredSearchInput.value;
-      const rightPos = inputValue.slice(selectionStart).search(/\s/);
-      if (rightPos < 0) {
+      const { right } = gl.DropdownUtils.getInputSelectionPosition(filteredSearchInput);
+      if (right < 0) {
         return inputValue;
       }
-      return inputValue.slice(0, rightPos + selectionStart + 1).trim();
+      return inputValue.slice(0, right + selectionStart + 1).trim();
+    }
+
+    static getInputSelectionPosition(input) {
+      const inputValue = input.value;
+      const selectionStart = input.selectionStart;
+      const left = inputValue.slice(0, selectionStart + 1).search(/\S+$/);
+      const right = inputValue.slice(selectionStart).search(/\s/);
+
+      return {
+        left,
+        right,
+      };
     }
   }

app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js.es6

@@ -57,29 +57,23 @@
     static addWordToInput(tokenName, tokenValue = '') {
       const input = document.querySelector('.filtered-search');
+      const inputValue = input.value;
       const word = `${tokenName}:${tokenValue}`;
-      const inputValue = gl.DropdownUtils.getSearchInput(input).trim();
-      const { lastToken, searchToken } = gl.FilteredSearchTokenizer.processTokens(inputValue);
-      const lastSearchToken = searchToken.split(' ').last();
-      const lastInputCharacter = input.value[input.value.length - 1];
-      const lastInputTrimmedCharacter = input.value.trim()[input.value.trim().length - 1];
-
-      // Remove the typed tokenName
-      if (word.indexOf(lastSearchToken) === 0 && searchToken !== '') {
-        // Remove spaces after the colon
-        if (lastInputCharacter === ' ' && lastInputTrimmedCharacter === ':') {
-          input.value = input.value.trim();
-        }
-
-        input.value = input.value.slice(0, -1 * lastSearchToken.length);
-      } else if (lastInputCharacter !== ' ' || (lastToken && lastToken.value[lastToken.value.length - 1] === ' ')) {
-        // Remove the existing tokenValue
-        const lastTokenString = `${lastToken.key}:${lastToken.symbol}${lastToken.value}`;
-        input.value = input.value.slice(0, -1 * lastTokenString.length);
+      // Get the string to replace
+      const selectionStart = input.selectionStart;
+      const { left } = gl.DropdownUtils.getInputSelectionPosition(input);
+      let { right } = gl.DropdownUtils.getInputSelectionPosition(input);
+
+      if (right < 0) {
+        right = inputValue.length;
       }
-      input.value += word;
+      if (left !== -1) {
+        input.value = `${inputValue.substr(0, left)}${word}${inputValue.substr(right + selectionStart)}`;
+      } else {
+        input.value += word;
+      }
     }
     updateCurrentDropdownOffset() {
@@ -93,7 +87,8 @@
       const filterIconPadding = 27;
       const offset = gl.text
-        .getTextWidth(gl.DropdownUtils.getSearchInput(this.filteredSearchInput).trim(), this.font) + filterIconPadding;
+        .getTextWidth(gl.DropdownUtils.getSearchInput(this.filteredSearchInput).trim(), this.font)
+        + filterIconPadding;
       this.mapping[key].reference.setOffset(offset);
     }

app/assets/javascripts/filtered_search/filtered_search_manager.js.es6

@@ -193,7 +193,8 @@
     }
     showOnClick() {
-      const currentDropdownRef = this.dropdownManager.mapping[this.dropdownManager.currentDropdown].reference;
+      const dropdown = this.dropdownManager.mapping[this.dropdownManager.currentDropdown];
+      const currentDropdownRef = dropdown.reference;
       this.setDropdownWrapper();
       currentDropdownRef.dispatchInputEvent();