search: Empty input on open, and show current narrow search suggestions.

Fixes #30911

web/e2e-tests/message-basics.test.ts

@@ -179,8 +179,6 @@ async function search_and_check(
 ): Promise<void> {
     await page.click(".search_icon");
     await page.waitForSelector(".navbar-search.expanded", {visible: true});
-    // Close the "in: home" pill
-    await page.click(".navbar-search .pill-close-button");
     await common.select_item_via_typeahead(page, "#search_query", search_str, item_to_select);
     // Enter to trigger search
     await page.keyboard.press("Enter");
@@ -193,8 +191,6 @@ async function search_and_check(
 async function search_silent_user(page: Page, str: string, item: string): Promise<void> {
     await page.click(".search_icon");
     await page.waitForSelector(".navbar-search.expanded", {visible: true});
-    // Close the "in: home" pill
-    await page.click(".navbar-search .pill-close-button");
     await common.select_item_via_typeahead(page, "#search_query", str, item);
     // Enter to trigger search
     await page.keyboard.press("Enter");

web/src/search.ts

@@ -6,7 +6,6 @@ import render_search_list_item from "../templates/search_list_item.hbs";
 import {Typeahead} from "./bootstrap_typeahead";
 import type {TypeaheadInputElement} from "./bootstrap_typeahead";
 import {Filter} from "./filter";
-import type {RemovePillTrigger} from "./input_pill";
 import * as keydown_util from "./keydown_util";
 import * as narrow_state from "./narrow_state";
 import * as popovers from "./popovers";
@@ -168,7 +167,13 @@ export function initialize(opts: {on_narrow_search: OnNarrowSearch}): void {
             assert(search_pill_widget !== null);
             const query_from_pills =
                 search_pill.get_current_search_string_for_widget(search_pill_widget);
-            const suggestions = search_suggestion.get_suggestions(query_from_pills, query);
+            const add_current_filter =
+                query_from_pills === "" && narrow_state.filter() !== undefined;
+            const suggestions = search_suggestion.get_suggestions(
+                query_from_pills,
+                query,
+                add_current_filter,
+            );
             // Update our global search_map hash
             search_map = suggestions.lookup_table;
             return suggestions.strings;
@@ -361,7 +366,7 @@ export function initialize(opts: {on_narrow_search: OnNarrowSearch}): void {
 }
 
 export function initiate_search(): void {
-    open_search_bar_and_close_narrow_description();
+    open_search_bar_and_close_narrow_description(true);
     focus_search_input_at_end();
 
     // Open the typeahead after opening the search bar, so that we don't
@@ -372,15 +377,17 @@ export function initiate_search(): void {
 
 // we rely entirely on this function to ensure
 // the searchbar has the right text/pills.
-function reset_searchbox(): void {
+function reset_searchbox(clear = false): void {
     assert(search_pill_widget !== null);
     search_pill_widget.clear(true);
     search_input_has_changed = false;
+    if (!clear) {
         search_pill.set_search_bar_contents(
             narrow_state.search_terms(),
             search_pill_widget,
             set_search_bar_text,
         );
+    }
 }
 
 function exit_search(opts: {keep_search_narrow_open: boolean}): void {
@@ -399,8 +406,8 @@ function exit_search(opts: {keep_search_narrow_open: boolean}): void {
     $(".app").trigger("focus");
 }
 
-export function open_search_bar_and_close_narrow_description(): void {
+export function open_search_bar_and_close_narrow_description(clear = false): void {
-    reset_searchbox();
+    reset_searchbox(clear);
     $(".navbar-search").addClass("expanded");
     $("#message_view_header").addClass("hidden");
     popovers.hide_all();

web/src/search_suggestion.ts

@@ -842,13 +842,51 @@ function suggestion_search_string(suggestion_line: SuggestionLine): string {
     return search_strings.join(" ");
 }
 
+function suggestions_for_current_filter(): SuggestionLine[] {
+    if (narrow_state.stream_name() && narrow_state.topic() !== "") {
+        return [
+            get_default_suggestion_line([
+                {
+                    operator: "channel",
+                    operand: narrow_state.stream_name()!,
+                },
+            ]),
+            get_default_suggestion_line(narrow_state.search_terms()),
+        ];
+    }
+    if (narrow_state.pm_emails_string()) {
+        return [
+            get_default_suggestion_line([
+                {
+                    operator: "is",
+                    operand: "dm",
+                },
+            ]),
+            get_default_suggestion_line(narrow_state.search_terms()),
+        ];
+    }
+    return [get_default_suggestion_line(narrow_state.search_terms())];
+}
+
 class Attacher {
     result: SuggestionLine[] = [];
     prev = new Set<string>();
     base: SuggestionLine;
+    add_current_filter: boolean;
 
-    constructor(base: SuggestionLine) {
+    constructor(base: SuggestionLine, search_query_is_empty: boolean, add_current_filter: boolean) {
         this.base = base;
+        this.add_current_filter = add_current_filter;
+        // Sometimes we add suggestions with the current filter in case
+        // the user wants to search within the current filter. For an empty
+        // search query, we put the current filter suggestions at the start
+        // of the list.
+        if (search_query_is_empty && this.add_current_filter) {
+            this.add_current_filter = false;
+            for (const current_filter_line of suggestions_for_current_filter()) {
+                this.push(current_filter_line);
+            }
+        }
     }
 
     push(suggestion_line: SuggestionLine): void {
@@ -926,7 +964,11 @@ class Attacher {
     }
 }
 
-export function get_search_result(query_from_pills: string, query_from_text: string): Suggestion[] {
+export function get_search_result(
+    query_from_pills: string,
+    query_from_text: string,
+    add_current_filter = false,
+): Suggestion[] {
     let suggestion_line: SuggestionLine;
 
     // search_terms correspond to the terms for the query in the input.
@@ -971,7 +1013,7 @@ export function get_search_result(query_from_pills: string, query_from_text: str
 
     const base_terms = [...pill_search_terms, ...text_search_terms.slice(0, -1)];
     const base = get_default_suggestion_line(base_terms);
-    const attacher = new Attacher(base);
+    const attacher = new Attacher(base, all_search_terms.length === 0, add_current_filter);
 
     // Display the default first, unless it has invalid terms.
     if (last.operator === "search") {
@@ -1055,11 +1097,12 @@ export function get_search_result(query_from_pills: string, query_from_text: str
 export function get_suggestions(
     query_from_pills: string,
     query_from_text: string,
+    add_current_filter = false,
 ): {
     strings: string[];
     lookup_table: Map<string, Suggestion>;
 } {
-    const result = get_search_result(query_from_pills, query_from_text);
+    const result = get_search_result(query_from_pills, query_from_text, add_current_filter);
     return finalize_search_result(result);
 }