🏗️🔧：stop a filename being read as an option

build/utils.mts

@@ -38,7 +38,17 @@ export const exec = catchWrap(execute, 99);
 export const quote = (paths: string | string[]) =>
   [paths]
     .flat()
-    .map((path) => `'${path.replaceAll("'", "'\\''")}'`)
+    .map((path) => {
+      // Quoting settles what the shell does with a name and nothing about
+      // what the tool then makes of it: `'--write.md'` arrives at prettier as
+      // `--write.md`, which it reads as an option. It answered that one by
+      // printing an error and exiting 0 -- a check that passed having checked
+      // nothing. A leading `./` says the argument is a path and costs a
+      // relative name two characters.
+      const safe = path.startsWith('-') ? `./${path}` : path;
+
+      return `'${safe.replaceAll("'", "'\\''")}'`;
+    })
     .join(' ');
 
 /**

build/utils.test.mts

@@ -140,6 +140,17 @@ describe('quote', () => {
     deepStrictEqual(quote("it's.md"), "'it'\\''s.md'");
   });
 
+  test('keeps a name that looks like an option from being read as one', () => {
+    // Quoting alone leaves `--write.md` arriving at the tool as `--write.md`.
+    deepStrictEqual(quote('--write.md'), "'./--write.md'");
+    deepStrictEqual(quote('-'), "'./-'");
+  });
+
+  test('leaves an ordinary path alone', () => {
+    deepStrictEqual(quote('doc/adr/0001-a.md'), "'doc/adr/0001-a.md'");
+    deepStrictEqual(quote('/abs/path.jar'), "'/abs/path.jar'");
+  });
+
   test('survives a round trip through the shell it is written for', async () => {
     // The escaping is only worth anything if the shell `exec` uses agrees
     // with it, so this asks that shell rather than a model of it.