Feedback round 1 applied

Add note around intentional marker spacing,
refactor to wrap/unwrap fns fs isWrap flag,
and updated spec to be more robust example

app/assets/javascripts/static_site_editor/components/edit_area.vue

@@ -62,7 +62,9 @@ export default {
   methods: {
     preProcess(isWrap, value) {
       const formattedContent = formatter(value);
-      const templatedContent = templater(isWrap, formattedContent);
+      const templatedContent = isWrap
+        ? templater.wrap(formattedContent)
+        : templater.unwrap(formattedContent);
       return templatedContent;
     },
     onInputChange(newVal) {

app/assets/javascripts/static_site_editor/services/templater.js

-// eslint-disable-next-line @gitlab/require-i18n-strings
-const marker = ' sse';
+const marker = 'sse';
 const ticks = '```';
-const prefix = `${ticks}${marker}\n`;
+const prefix = `${ticks} ${marker}\n`; // Space intentional due to https://github.com/nhn/tui.editor/blob/6bcec75c69028570d93d973aa7533090257eaae0/libs/to-mark/src/renderer.gfm.js#L26
 const postfix = `\n${ticks}`;
 const code = '.| |\\t|\\n(?!\\n)';
 const templatedRegex = new RegExp(`(^${prefix}(${code})+${postfix}$)`, 'gm');
@@ -30,6 +29,4 @@ const wrap = source => {
   return text;
 };
 
-const template = (isWrap, source) => (isWrap ? wrap(source) : unwrap(source));
-
-export default template;
+export default { wrap, unwrap };

spec/frontend/static_site_editor/services/templater_spec.js

+/* eslint-disable no-useless-escape */
 import templater from '~/static_site_editor/services/templater';
 
 describe('templater', () => {
@@ -6,6 +7,12 @@ describe('templater', () => {
 <% some erb code %>
 
 Some more text
+
+<% if apptype.maturity && (apptype.maturity != "planned") %>
+  <% maturity = "This application type is at the \"#{apptype.maturity}\" level of maturity." %>
+<% end %>
+
+With even text with indented code above.
 `;
   const sourceTemplated = `Some text
 
@@ -14,18 +21,26 @@ Some more text
 \`\`\`
 
 Some more text
+
+\`\`\` sse
+<% if apptype.maturity && (apptype.maturity != "planned") %>
+  <% maturity = "This application type is at the \"#{apptype.maturity}\" level of maturity." %>
+<% end %>
+\`\`\`
+
+With even text with indented code above.
 `;
 
   it.each`
-    isWrap   | initial            | target
-    ${true}  | ${source}          | ${sourceTemplated}
-    ${true}  | ${sourceTemplated} | ${sourceTemplated}
-    ${false} | ${sourceTemplated} | ${source}
-    ${false} | ${source}          | ${source}
+    fn          | initial            | target
+    ${'wrap'}   | ${source}          | ${sourceTemplated}
+    ${'wrap'}   | ${sourceTemplated} | ${sourceTemplated}
+    ${'unwrap'} | ${sourceTemplated} | ${source}
+    ${'unwrap'} | ${source}          | ${source}
   `(
-    'wraps $initial in a templated sse codeblock when $isWrap and unwraps otherwise',
-    ({ isWrap, initial, target }) => {
-      expect(templater(isWrap, initial)).toMatch(target);
+    'wraps $initial in a templated sse codeblock if $fn is wrap, unwraps otherwise',
+    ({ fn, initial, target }) => {
+      expect(templater[fn](initial)).toMatch(target);
     },
   );
 });