restore tea finds prefix if properly installed

Author: mxcl

README.md

@@ -16,7 +16,7 @@
 </p>
 
 
-# tea/cli 0.33.0
+# tea/cli 0.33.1
 
 `tea` puts the whole open source ecosystem at your fingertips:
 

src/hooks/useConfig.ts

@@ -49,6 +49,18 @@ export default function(input?: Config): Config {
 }
 
 export function ConfigDefault(flags?: Flags, arg0 = Deno.execPath(), env = Deno.env.toObject()): Config {
+  if (!env['TEA_PREFIX']) {
+    const shelf = new Path(arg0)
+      .readlink() // resolves the leaf symlink (if any)
+      .parent()
+      .parent()
+      .parent()
+
+    if (shelf.basename() == 'tea.xyz') {
+      env['TEA_PREFIX'] = shelf.parent().string
+    }
+  }
+
   const defaults = ConfigBaseDefault(env)
 
   const {

tests/unit/useConfig.test.ts

@@ -0,0 +1,39 @@
+import useConfig, { ConfigDefault } from "../../src/hooks/useConfig.ts"
+import { assertEquals } from "deno/testing/asserts.ts"
+import { _internals } from "tea/hooks/useConfig.ts"
+import { Path } from "tea"
+
+Deno.test("prefix discovery", async () => {
+  const tmp = new Path(await Deno.makeTempDir())
+  const tea = tmp.join("tea.xyz/v1.2.3/bin").mkdir('p').join("tea").touch()
+  const config = ConfigDefault(undefined, tea.string, {})
+  assertEquals(config.prefix, tmp)
+})
+
+Deno.test("prefix discovery via versioned symlink", async () => {
+  const tmp = new Path(await Deno.makeTempDir())
+  const shelf = tmp.join("tea.xyz")
+  const keg = shelf.join("v1.2.3")
+
+  keg.join("bin").mkdir('p').join("tea").touch()
+
+  const v1 = shelf.join("v1").ln('s', { target: keg })
+  const config = ConfigDefault(undefined, v1.join('bin/tea').string, {})
+  assertEquals(config.prefix, tmp)
+})
+
+Deno.test("prefix discovery via separate symlink", async () => {
+  const tmp = new Path(await Deno.makeTempDir())
+  const tea = tmp.join('tea').ln('s', { target: tmp.join("tea.xyz/v1.2.3/bin").mkdir('p').join("tea").touch() })
+
+  const config = ConfigDefault(undefined, tea.string, {})
+  assertEquals(config.prefix, tmp)
+})
+
+Deno.test("prefix discovery defaults to ~/.tea", async () => {
+  const tmp = new Path(await Deno.makeTempDir())
+  const tea = tmp.join('tea').touch()
+
+  const config = ConfigDefault(undefined, tea.string, {})
+  assertEquals(config.prefix, Path.home().join(".tea"))
+})