From 1eb6d179be81553027d31c0bfeb2f989694605c6 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Sat, 26 Aug 2023 01:16:22 -0400
Subject: [PATCH] Add helpers for working with words

---
 src/words.test.ts | 60 +++++++++++++++++++++++++++++++++++++++++++++++
 src/words.ts      | 44 ++++++++++++++++++++++++++++++----
 2 files changed, 99 insertions(+), 5 deletions(-)
 create mode 100644 src/words.test.ts

diff --git a/src/words.test.ts b/src/words.test.ts
new file mode 100644
index 0000000..f55bdb8
--- /dev/null
+++ b/src/words.test.ts
@@ -0,0 +1,60 @@
+import { AsHtml, AsText, Concat } from "./words";
+
+describe("Text Words", () => {
+  test.each([
+    [{ enchanted: "apple" }, "apple"],
+    [{ enchanted: "<pie>" }, "<pie>"],
+    [{ text: "banana" }, "banana"],
+    [{ text: "<b>kiwi" }, "<b>kiwi"],
+    [{ html: "<b>cherry</b>" }, "<b>cherry</b>"],
+  ])("AsText(%s)", (word, expected) => expect(AsText(word)).toEqual(expected));
+
+  test.each([
+    [{ enchanted: "apple" }, "apple"],
+    [{ enchanted: "<pie>" }, "&lt;pie&gt;"],
+    [{ text: "banana" }, "banana"],
+    [{ text: "<b>kiwi" }, "&lt;b&gt;kiwi"],
+    [{ html: "<b>cherry</b>" }, "<b>cherry</b>"],
+  ])("AsHtml(%s)", (word, expected) => expect(AsHtml(word)).toEqual(expected));
+
+  test.each([
+    [null, { enchanted: "1" }, { text: "1" }],
+    [null, { enchanted: ">1" }, { text: ">1" }],
+    [null, { text: "2" }, { text: "2" }],
+    [null, { text: "<b>3</b>" }, { text: "<b>3</b>" }],
+    [null, { html: "2" }, { html: "2" }],
+    [null, { html: "<b>3</b>" }, { html: "<b>3</b>" }],
+    [{ enchanted: "&pple" }, { enchanted: "1" }, { text: "&pple1" }],
+    [{ enchanted: "&pple" }, { enchanted: ">1" }, { text: "&pple>1" }],
+    [{ enchanted: "&pple" }, { text: "2" }, { text: "&pple2" }],
+    [{ enchanted: "&pple" }, { text: "<b>3</b>" }, { text: "&pple<b>3</b>" }],
+    [{ enchanted: "&pple" }, { html: "2" }, { html: "&amp;pple2" }],
+    [
+      { enchanted: "&pple" },
+      { html: "<b>3</b>" },
+      { html: "&amp;pple<b>3</b>" },
+    ],
+    [{ text: "<b>anana" }, { enchanted: "1" }, { text: "<b>anana1" }],
+    [{ text: "<b>anana" }, { enchanted: ">1" }, { text: "<b>anana>1" }],
+    [{ text: "<b>anana" }, { text: "2" }, { text: "<b>anana2" }],
+    [{ text: "<b>anana" }, { text: "<b>3</b>" }, { text: "<b>anana<b>3</b>" }],
+    [{ text: "<b>anana" }, { html: "2" }, { html: "&lt;b&gt;anana2" }],
+    [
+      { text: "<b>anana" },
+      { html: "<b>3</b>" },
+      { html: "&lt;b&gt;anana<b>3</b>" },
+    ],
+    [{ html: "<img />" }, { enchanted: "1" }, { html: "<img />1" }],
+    [{ html: "<img />" }, { enchanted: ">1" }, { html: "<img />&gt;1" }],
+    [{ html: "<img />" }, { text: "2" }, { html: "<img />2" }],
+    [
+      { html: "<img />" },
+      { text: "<b>3</b>" },
+      { html: "<img />&lt;b&gt;3&lt;/b&gt;" },
+    ],
+    [{ html: "<img />" }, { html: "2" }, { html: "<img />2" }],
+    [{ html: "<img />" }, { html: "<b>3</b>" }, { html: "<img /><b>3</b>" }],
+  ])("Concat(%s, %s)", (left, right, expected) =>
+    expect(Concat(left, right)).toEqual(expected)
+  );
+});
diff --git a/src/words.ts b/src/words.ts
index 151a2fb..31e26e8 100644
--- a/src/words.ts
+++ b/src/words.ts
@@ -1,3 +1,5 @@
+import { escapeHtml } from "./helpers";
+
 /**
  * A word whose value is text with provenance- this literal value appeared in the source
  * code, and was not the result of any backslash, variable, or command substitutions.
@@ -29,7 +31,7 @@ export type HtmlWord = {
   html: string;
 };
 
-export type TextPiece = TextWord;
+export type TextPiece = EnchantedWord | TextWord | HtmlWord;
 export type VariablePiece = { variable: string };
 export type ScriptPiece = { script: Script };
 export type InterpolatedPiece = TextPiece | VariablePiece | ScriptPiece;
@@ -42,18 +44,50 @@ export type InterpolatedWord = {
   pieces: InterpolatedPiece[];
 };
 
+export function AsText(word: TextPiece): string {
+  if ("enchanted" in word) {
+    return word.enchanted;
+  } else if ("text" in word) {
+    return word.text;
+  } else if ("html" in word) {
+    return word.html;
+  } else {
+    return "";
+  }
+}
+export function AsHtml(word: TextPiece): string {
+  if ("enchanted" in word) {
+    return escapeHtml(word.enchanted);
+  } else if ("text" in word) {
+    return escapeHtml(word.text);
+  } else if ("html" in word) {
+    return word.html;
+  } else {
+    return "";
+  }
+}
+
 // safely concatenate text pieces, converting as needed
-export function Concat(left: TextPiece, right: TextPiece) {
-  return { text: left.text + right.text };
+export function Concat(left: TextPiece | null, right: TextPiece) {
+  if (left === null) {
+    return "enchanted" in right ? { text: right.enchanted } : right;
+  }
+  if ("html" in left || "html" in right) {
+    return { html: AsHtml(left) + AsHtml(right) };
+  } else {
+    return { text: AsText(left) + AsText(right) };
+  }
 }
 
 function IsTextPiece(piece: InterpolatedPiece | undefined): piece is TextPiece {
-  return piece ? "text" in piece : false;
+  return piece
+    ? "text" in piece || "enchanted" in piece || "html" in piece
+    : false;
 }
 
 export function SimplifyWord(
   pieces: InterpolatedPiece[]
-): InterpolatedWord | TextWord {
+): InterpolatedWord | EnchantedWord | TextWord | HtmlWord {
   const consolidated: InterpolatedPiece[] = [];
   for (const piece of pieces) {
     const top = consolidated[consolidated.length - 1];