From 6a6b55b79b9733913010454ed4beda0694e6cacf Mon Sep 17 00:00:00 2001
From: William So <polyipseity@gmail.com>
Date: Thu, 6 Jun 2024 14:10:47 +0800
Subject: [PATCH] Change `.open` to use feature detection instead

Signed-off-by: William So <polyipseity@gmail.com>
---
 .changeset/yellow-islands-laugh.md |  5 +++++
 sources/@types/obsidian.ts         |  8 +++-----
 sources/obsidian.ts                | 17 ++++++++---------
 3 files changed, 16 insertions(+), 14 deletions(-)
 create mode 100644 .changeset/yellow-islands-laugh.md

diff --git a/.changeset/yellow-islands-laugh.md b/.changeset/yellow-islands-laugh.md
new file mode 100644
index 0000000..48a2b04
--- /dev/null
+++ b/.changeset/yellow-islands-laugh.md
@@ -0,0 +1,5 @@
+---
+"@polyipseity/obsidian-plugin-library": minor
+---
+
+Change `$FileSystem.open` to use feature detection instead.
diff --git a/sources/@types/obsidian.ts b/sources/@types/obsidian.ts
index 40bd6eb..9a41511 100644
--- a/sources/@types/obsidian.ts
+++ b/sources/@types/obsidian.ts
@@ -33,8 +33,6 @@ import type {
 	SettingTab,
 	UnknownSettingTab,
 } from "obsidian"
-import type { Deopaque } from "../types.js"
-import type { Platform } from "../platform.js"
 import type { Private } from "../private.js"
 
 declare const PRIVATE_KEY: unique symbol
@@ -67,9 +65,9 @@ interface $DataAdapter {
 }
 
 interface $FileSystem {
-	readonly open: <T extends Platform.Current>(
-		path: Deopaque<T> extends Platform.Mobile ? string : never,
-	) => Deopaque<T> extends Platform.Mobile ? PromiseLike<void> : never
+	readonly open?: <Length extends number>(
+		path: Length extends 1 ? string : never,
+	) => Length extends 1 ? PromiseLike<void> : never
 }
 
 interface $Plugins {
diff --git a/sources/obsidian.ts b/sources/obsidian.ts
index a3b9dd4..6c71f89 100644
--- a/sources/obsidian.ts
+++ b/sources/obsidian.ts
@@ -30,7 +30,6 @@ import {
 	cloneAsWritable,
 	createChildElement,
 	deepFreeze,
-	inSet,
 	instanceOf,
 	multireplace,
 	onVisible,
@@ -40,7 +39,6 @@ import { cloneDeep, constant, noop } from "lodash-es"
 import { revealPrivate, revealPrivateAsync } from "./private.js"
 import type { AsyncOrSync } from "ts-essentials"
 import { InternalDOMClasses } from "./internals/magic.js"
-import { Platform } from "./platform.js"
 import type { PluginContext } from "./plugin.js"
 import { around } from "monkey-around"
 import { saveAs } from "file-saver"
@@ -486,10 +484,10 @@ export async function saveFileAs(
 	adapter: DataAdapter,
 	data: File,
 ): Promise<void> {
-	const { CURRENT, MOBILE } = Platform
-	if (inSet(MOBILE, CURRENT)) {
-		await revealPrivateAsync(context, [adapter], async ({ fs }) => {
-			await fs.open<typeof CURRENT>(
+	if (await revealPrivateAsync(context, [adapter], async ({ fs }) => {
+		if ("open" in fs && fs.open.length === 1) {
+			const { length } = fs.open
+			await fs.open<typeof length>(
 				(await Filesystem.writeFile({
 					data: await data.text(),
 					directory: Directory.Cache,
@@ -497,9 +495,10 @@ export async function saveFileAs(
 					path: data.name,
 				})).uri,
 			)
-		}, noop)
-		return
-	}
+			return true
+		}
+		return false
+	}, constant(false))) { return }
 	saveAs(data)
 }