Implement deselect_completion ex command

Left unbound by default.

src/commandline_frame.ts

@@ -209,6 +209,13 @@ export function prev_completion() {
     if (activeCompletions) activeCompletions.forEach(comp => comp.prev())
 }
 
+/**
+ * Deselects the currently selected completion.
+ */
+export function deselect_completion() {
+    if (activeCompletions) activeCompletions.forEach(comp => comp.deselect())
+}
+
 /**
  * Inserts the currently selected completion and a space in the command line.
  */

src/completions.ts

@@ -36,6 +36,7 @@ export abstract class CompletionSource {
     node: HTMLElement
     public completion: string
     protected prefixes: string[] = []
+    protected lastFocused: CompletionOption
 
     constructor(prefixes) {
         let commands = aliases.getCmdAliasMapping()
@@ -78,6 +79,11 @@ export abstract class CompletionSource {
     prev(inc = 1): boolean {
         return this.next(-1 * inc)
     }
+
+    deselect() {
+        this.completion = undefined
+        if (this.lastFocused != undefined) this.lastFocused.state = "normal"
+    }
 }
 
 // Default classes
@@ -129,7 +135,6 @@ export abstract class CompletionSourceFuse extends CompletionSource {
     public node
     public options: CompletionOptionFuse[]
     protected lastExstr: string
-    protected lastFocused: CompletionOption
 
     protected optionContainer = html`<table class="optionContainer">`
 
@@ -197,11 +202,6 @@ export abstract class CompletionSourceFuse extends CompletionSource {
         }
     }
 
-    deselect() {
-        this.completion = undefined
-        if (this.lastFocused != undefined) this.lastFocused.state = "normal"
-    }
-
     splitOnPrefix(exstr: string) {
         for (const prefix of this.prefixes) {
             if (exstr.startsWith(prefix)) {

src/excmds.ts

@@ -2606,14 +2606,15 @@ export async function fillcmdline_tmp(ms: number, ...strarr: string[]) {
 /** @hidden **/
 const cmdframe_fns: { [key: string]: [string, any[]] } = {
     accept_line: ["accept_line", []],
-    next_history: ["next_history", []],
-    prev_history: ["prev_history", []],
-    next_completion: ["next_completion", []],
-    prev_completion: ["prev_completion", []],
+    complete: ["complete", []],
+    deselect_completion: ["deselect_completion", []],
+    hide_and_clear: ["hide_and_clear", []],
     insert_completion: ["insert_completion", []],
     insert_space_or_completion: ["insert_space_or_completion", []],
-    complete: ["complete", []],
-    hide_and_clear: ["hide_and_clear", []],
+    next_completion: ["next_completion", []],
+    next_history: ["next_history", []],
+    prev_completion: ["prev_completion", []],
+    prev_history: ["prev_history", []],
 }
 
 import * as tri_editor from "@src/lib/editor"