records: a phrase that wraps, and one under emphasis, is found

The record is prose wrapped at a hundred columns; matched line by line, the first live search for a
sentence of ADR 0025 found nothing. A line is matched together with the next, emphasis marks are
ignored, and a hit still names the line it starts on.

modules/records/records.ts

@@ -153,9 +153,15 @@ export class Records {
    * Where a phrase appears, case-insensitively, as written — no stemming, no ranking, because a
    * design record is found by its own words and a reader deciding which words matter would be a
    * second opinion about somebody else's document. Bounded, and says when it was.
+   *
+   * **The record is wrapped prose, and a phrase does not know where the line ends.** Every document
+   * here wraps at a hundred columns, so a phrase of six words is as likely to straddle a line break
+   * as not; matched line by line, the first live search for a sentence of ADR 0025 found nothing.
+   * So a line is matched together with the one after it, joined by a space, and emphasis marks
+   * are ignored — `**reachable**` is the word reachable. A hit still names the line it starts on.
    */
   async search(query: string, limit = MOST_HITS): Promise<{ hits: Hit[]; more: boolean; commit: string }> {
-    const needle = query.trim().toLowerCase();
+    const needle = plain(query).toLowerCase().replace(/\s+/g, " ").trim();
     if (!needle) throw new Error("search for a phrase; an empty one matches every line of every document");
     const cap = Math.max(1, Math.min(limit, MOST_HITS));
     const hits: Hit[] = [];
@@ -164,15 +170,22 @@ export class Records {
       const text = await fs.readFile(join(this.dir, path), "utf8");
       let heading = "";
       const lines = text.split("\n");
+      const flat = lines.map((l) => plain(l).toLowerCase().replace(/\s+/g, " ").trim());
       for (let i = 0; i < lines.length; i++) {
         const line = lines[i]!;
         if (/^#{1,6}\s/.test(line)) heading = line.replace(/^#+\s*/, "").trim();
-        if (line.toLowerCase().includes(needle)) {
+        const here = flat[i]!;
+        const next = i + 1 < flat.length ? flat[i + 1]! : "";
+        // On this line, or across the break into the next — but not a phrase that begins on the
+        // next line alone, which is that line's hit.
+        const onThis = here.includes(needle);
+        const acrossTheBreak = !onThis && next !== "" && `${here} ${next}`.includes(needle) && !next.includes(needle);
+        if (onThis || acrossTheBreak) {
           if (hits.length >= cap) {
             more = true;
             break;
           }
-          hits.push({ path, line: i + 1, heading, text: line.trim() });
+          hits.push({ path, line: i + 1, heading, text: acrossTheBreak ? `${line.trim()} ${lines[i + 1]!.trim()}` : line.trim() });
         }
       }
       if (more) break;
@@ -249,6 +262,11 @@ export async function recordsFromEnv(env: NodeJS.ProcessEnv = process.env): Prom
   return new Records(dir, origin, repository);
 }
 
+/** A line without its markdown emphasis, so a phrase matches the words and not the marks. */
+function plain(line: string): string {
+  return line.replace(/[*_`]/g, "");
+}
+
 async function exists(path: string): Promise<boolean> {
   try {
     await fs.stat(path);