Make SearchCursor ignore matches that match only part of a normalized…

… character

FIX: Fix an issue in `SearchCursor` where character normalization could produce nonsensical matches.

Closes codemirror/dev#1219

src/cursor.ts

@@ -77,11 +77,13 @@ export class SearchCursor implements Iterator<{from: number, to: number}>{
       for (let i = 0, pos = start;; i++) {
         let code = norm.charCodeAt(i)
         let match = this.match(code, pos)
-        if (match) {
-          this.value = match
-          return this
-         }
-        if (i == norm.length - 1) break
+        if (i == norm.length - 1) {
+          if (match) {
+            this.value = match
+            return this
+          }
+          break
+        }
         if (pos == start && i < str.length && str.charCodeAt(i) == code) pos++
       }
     }

test/test-cursor.ts

@@ -60,6 +60,10 @@ describe("SearchCursor", () => {
     while (!cursor.nextOverlapping().done) matches.push([cursor.value.from, cursor.value.to])
     ist(JSON.stringify(matches), "[[0,4],[2,6],[4,8]]")
   })
+
+  it("will not match partial normalized content", () => {
+    testMatches(new SearchCursor(Text.of(["´"]), " "), [])
+  })
 })
 
 describe("RegExpCursor", () => {