1 files changed, 110 insertions, 0 deletions
diff --git a/packages/bun-inspector-protocol/src/util/preview.ts b/packages/bun-inspector-protocol/src/util/preview.ts
new file mode 100644
index 000000000..ad751a2b8
--- /dev/null
+++ b/packages/bun-inspector-protocol/src/util/preview.ts
@@ -0,0 +1,110 @@
+import type { JSC } from "../protocol";
+
+export function remoteObjectToString(remoteObject: JSC.Runtime.RemoteObject): string {
+  const { type, subtype, value, description, className, preview } = remoteObject;
+  switch (type) {
+    case "undefined":
+      return "undefined";
+    case "boolean":
+    case "number":
+      return description ?? JSON.stringify(value);
+    case "string":
+      return JSON.stringify(value ?? description);
+    case "symbol":
+    case "bigint":
+      return description!;
+    case "function":
+      return description!.replace("function", "ƒ") || "ƒ";
+  }
+  switch (subtype) {
+    case "null":
+      return "null";
+    case "regexp":
+    case "date":
+    case "error":
+      return description!;
+  }
+  if (preview) {
+    return objectPreviewToString(preview);
+  }
+  if (className) {
+    return className;
+  }
+  return description || "Object";
+}
+
+export function objectPreviewToString(objectPreview: JSC.Runtime.ObjectPreview): string {
+  const { type, subtype, entries, properties, overflow, description, size } = objectPreview;
+  if (type !== "object") {
+    return remoteObjectToString(objectPreview);
+  }
+  let items: string[];
+  if (entries) {
+    items = entries.map(entryPreviewToString).sort();
+  } else if (properties) {
+    if (isIndexed(subtype)) {
+      items = properties.map(indexedPropertyPreviewToString).sort();
+    } else {
+      items = properties.map(namedPropertyPreviewToString).sort();
+    }
+  } else {
+    items = ["…"];
+  }
+  if (overflow) {
+    items.push("…");
+  }
+  let label: string;
+  if (description === "Object") {
+    label = "";
+  } else if (size === undefined) {
+    label = description!;
+  } else {
+    label = `${description}(${size})`;
+  }
+  if (!items.length) {
+    return label || "{}";
+  }
+  if (label) {
+    label += " ";
+  }
+  if (isIndexed(subtype)) {
+    return `${label}[${items.join(", ")}]`;
+  }
+  return `${label}{${items.join(", ")}}`;
+}
+
+function propertyPreviewToString(propertyPreview: JSC.Runtime.PropertyPreview): string {
+  const { type, value, ...preview } = propertyPreview;
+  if (type === "accessor") {
+    return "ƒ";
+  }
+  return remoteObjectToString({ ...preview, type, description: value });
+}
+
+function entryPreviewToString(entryPreview: JSC.Runtime.EntryPreview): string {
+  const { key, value } = entryPreview;
+  if (key) {
+    return `${objectPreviewToString(key)} => ${objectPreviewToString(value)}`;
+  }
+  return objectPreviewToString(value);
+}
+
+function namedPropertyPreviewToString(propertyPreview: JSC.Runtime.PropertyPreview): string {
+  const { name, valuePreview } = propertyPreview;
+  if (valuePreview) {
+    return `${name}: ${objectPreviewToString(valuePreview)}`;
+  }
+  return `${name}: ${propertyPreviewToString(propertyPreview)}`;
+}
+
+function indexedPropertyPreviewToString(propertyPreview: JSC.Runtime.PropertyPreview): string {
+  const { valuePreview } = propertyPreview;
+  if (valuePreview) {
+    return objectPreviewToString(valuePreview);
+  }
+  return propertyPreviewToString(propertyPreview);
+}
+
+function isIndexed(type?: JSC.Runtime.RemoteObject["subtype"]): boolean {
+  return type === "array" || type === "set" || type === "weakset";
+}