Allow * and _ characters in Search AST 'word's (#1058)

* Allow * and _ characters in Search AST 'word's

* changelog

CHANGELOG.md

@@ -3,6 +3,7 @@
 - Added `spacesApp` logo to `EuiIcon` set ([#1065](https://github.com/elastic/eui/pull/1065))
 - Added `!default` to border SASS props ([#1079](https://github.com/elastic/eui/pull/1079))
 - Added `repositionOnScroll` prop to `EuiPopover` which enables repositioning the popover when the window is scrolled. ([#1064](https://github.com/elastic/eui/pull/1064))
+- Allow `_` and `*` characters to be used in `EuiSearchBar` query terms ([#1058](https://github.com/elastic/eui/pull/1058))
 
 **Bug fixes**
 

src/components/search_bar/query/default_syntax.js

@@ -127,7 +127,7 @@ word
 
 wordChar
   = alnum
-  / [-]
+  / [-_*]
   / escapedChar
 
 escapedChar

src/components/search_bar/query/default_syntax.test.js

@@ -661,6 +661,38 @@ describe('defaultSyntax', () => {
     expect(clause.value).toBe('truest');
   });
 
+  describe('wordChar', () => {
+    test('alphanumeric characters', () => {
+      const ast = defaultSyntax.parse('logstash');
+      const clauses = ast.getTermClauses();
+      expect(clauses).toEqual([{
+        type: 'term',
+        value: 'logstash',
+        match: 'must',
+      }]);
+    });
+
+    test('escaped characters', () => {
+      const ast = defaultSyntax.parse('\\-');
+      const clauses = ast.getTermClauses();
+      expect(clauses).toEqual([{
+        type: 'term',
+        value: '-',
+        match: 'must',
+      }]);
+    });
+
+    test('special characters', () => {
+      const ast = defaultSyntax.parse('*_-');
+      const clauses = ast.getTermClauses();
+      expect(clauses).toEqual([{
+        type: 'term',
+        value: '*_-',
+        match: 'must',
+      }]);
+    });
+  });
+
   test('number range expressions', () => {
 
     const query = `num1>6 -num2>=8 num3<4 -num4<=2`;