docs(manual): split testing into multiple chapters (#11067)

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/docs/testing/documentation.md b/docs/testing/documentation.md
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+# Documentation tests
+
+Deno supports type-checking your documentation examples.
+
+This makes sure that examples within your documentation are up to date and
+working.
+
+The basic idea is this:
+
+````ts
+/**
+ * # Examples
+ *
+ * ```ts
+ * const x = 42;
+ * ```
+ */
+````
+
+The triple backticks mark the start and end of code blocks.
+
+If this example was in a file named foo.ts, running `deno test --doc foo.ts`
+will extract this example, and then type-check it as a standalone module living
+in the same directory as the module being documented.
+
+To document your exports, import the module using a relative path specifier:
+
+````ts
+/**
+ * # Examples
+ *
+ * ```ts
+ * import { foo } from "./foo.ts";
+ * ```
+ */
+export function foo(): string {
+  return "foo";
+}
+````