feat(ext/console): Compact empty iterables when calling Deno.inspect with compact false (#14387)

2 files changed, 75 insertions, 4 deletions

diff --git a/cli/tests/unit/console_test.ts b/cli/tests/unit/console_test.ts
index 39baaf1a3..4601281ff 100644
--- a/cli/tests/unit/console_test.ts
+++ b/cli/tests/unit/console_test.ts
@@ -1939,6 +1939,71 @@ Deno.test(function inspectColors() {
   assertStringIncludes(Deno.inspect(1, { colors: true }), "\x1b[");
 });
 
+Deno.test(function inspectEmptyArray() {
+  const arr: string[] = [];
+
+  assertEquals(
+    Deno.inspect(arr, {
+      compact: false,
+      trailingComma: true,
+    }),
+    "[\n]",
+  );
+});
+
+Deno.test(function inspectDeepEmptyArray() {
+  const obj = {
+    arr: [],
+  };
+
+  assertEquals(
+    Deno.inspect(obj, {
+      compact: false,
+      trailingComma: true,
+    }),
+    `{
+  arr: [
+  ],
+}`,
+  );
+});
+
+Deno.test(function inspectEmptyMap() {
+  const map = new Map();
+
+  assertEquals(
+    Deno.inspect(map, {
+      compact: false,
+      trailingComma: true,
+    }),
+    "Map {\n}",
+  );
+});
+
+Deno.test(function inspectEmptyMap() {
+  const set = new Set();
+
+  assertEquals(
+    Deno.inspect(set, {
+      compact: false,
+      trailingComma: true,
+    }),
+    "Set {\n}",
+  );
+});
+
+Deno.test(function inspectEmptyMap() {
+  const typedArray = new Uint8Array(0);
+
+  assertEquals(
+    Deno.inspect(typedArray, {
+      compact: false,
+      trailingComma: true,
+    }),
+    "Uint8Array(0) [\n]",
+  );
+});
+
 Deno.test(function inspectStringAbbreviation() {
   const LONG_STRING =
     "This is a really long string which will be abbreviated with ellipsis.";
diff --git a/ext/console/02_console.js b/ext/console/02_console.js
index 607da2db6..9b54a64a1 100644
--- a/ext/console/02_console.js
+++ b/ext/console/02_console.js
@@ -465,12 +465,18 @@
     const entryIndentation = `,\n${
       StringPrototypeRepeat(DEFAULT_INDENT, level + 1)
     }`;
-    const closingIndentation = `${inspectOptions.trailingComma ? "," : ""}\n${
-      StringPrototypeRepeat(DEFAULT_INDENT, level)
-    }`;
+    const closingDelimIndentation = StringPrototypeRepeat(
+      DEFAULT_INDENT,
+      level,
+    );
+    const closingIndentation = `${
+      inspectOptions.trailingComma ? "," : ""
+    }\n${closingDelimIndentation}`;
 
     let iContent;
-    if (options.group && entries.length > MIN_GROUP_LENGTH) {
+    if (entries.length === 0 && !inspectOptions.compact) {
+      iContent = `\n${closingDelimIndentation}`;
+    } else if (options.group && entries.length > MIN_GROUP_LENGTH) {
       const groups = groupEntries(entries, level, value);
       iContent = `${initIndentation}${
         ArrayPrototypeJoin(groups, entryIndentation)