fix(self-update): add missing functions to self_update stub

src/cli/self_update_stub.rs

@@ -1,7 +1,49 @@
+use std::collections::BTreeMap;
+use std::fs;
+use std::path::PathBuf;
+
+use crate::env;
+
 pub struct SelfUpdate {}
 
 impl SelfUpdate {
     pub fn is_available() -> bool {
         false
     }
 }
+
+#[derive(Debug, Default, serde::Deserialize)]
+struct InstructionsToml {
+    message: Option<String>,
+    #[serde(flatten)]
+    commands: BTreeMap<String, String>,
+}
+
+fn read_instructions_file(path: &PathBuf) -> Option<String> {
+    let body = fs::read_to_string(path).ok()?;
+    let parsed: InstructionsToml = toml::from_str(&body).ok()?;
+    if let Some(msg) = parsed.message {
+        return Some(msg);
+    }
+    if let Some((_k, v)) = parsed.commands.into_iter().next() {
+        return Some(v);
+    }
+    None
+}
+
+pub fn upgrade_instructions_text() -> Option<String> {
+    if let Some(path) = &*env::MISE_SELF_UPDATE_INSTRUCTIONS {
+        if let Some(msg) = read_instructions_file(path) {
+            return Some(msg);
+        }
+    }
+    None
+}
+
+pub fn append_self_update_instructions(mut message: String) -> String {
+    if let Some(instructions) = upgrade_instructions_text() {
+        message.push('\n');
+        message.push_str(&instructions);
+    }
+    message
+}