feat(task): support env vars in task dependencies

docs/tasks/task-configuration.md

@@ -75,7 +75,7 @@ run = "cargo build"
 
 ### `depends`
 
-- **Type**: `string | string[]`
+- **Type**: `string | string[] | { task: string, args?: string[], env?: { [key]: string } }[]`
 
 Tasks that must be run before this task. This is a list of task names or aliases. Arguments can be
 passed to the task, e.g.: `depends = ["build --release"]`. If multiple tasks have the same dependency,
@@ -90,9 +90,46 @@ depends = ["build"]
 run = "cargo test"
 ```
 
+#### Passing environment variables to dependencies
+
+You can pass environment variables to specific dependencies using two syntaxes:
+
+**Shell-style inline:**
+
+```mise-toml
+[tasks.test]
+depends = ["NODE_ENV=test setup"]
+run = "npm test"
+
+[tasks.setup]
+run = 'echo "Setting up for $NODE_ENV"'
+```
+
+**Structured object format:**
+
+```mise-toml
+[tasks.test]
+depends = [
+  { task = "setup", env = { NODE_ENV = "test", DEBUG = "true" } }
+]
+run = "npm test"
+```
+
+The structured format also supports combining env vars with arguments:
+
+```mise-toml
+[tasks.deploy]
+depends = [
+  { task = "build", args = ["--release"], env = { RUSTFLAGS = "-C opt-level=3" } }
+]
+run = "./deploy.sh"
+```
+
+Note: These environment variables are passed only to the specified dependency, not to the current task or other dependencies.
+
 ### `depends_post`
 
-- **Type**: `string | string[]`
+- **Type**: `string | string[] | { task: string, args?: string[], env?: { [key]: string } }[]`
 
 Like `depends` but these tasks run _after_ this task and its dependencies complete. For example, you
 may want a `postlint` task that you can run individually without also running `lint`:
@@ -105,9 +142,11 @@ depends_post = ["postlint"]
 run = "echo 'linting complete'"
 ```
 
+Supports the same argument and environment variable syntax as `depends`.
+
 ### `wait_for`
 
-- **Type**: `string | string[]`
+- **Type**: `string | string[] | { task: string, args?: string[], env?: { [key]: string } }[]`
 
 Similar to `depends`, it will wait for these tasks to complete before running however they won't be
 added to the list of tasks to run. This is essentially optional dependencies.
@@ -118,6 +157,8 @@ wait_for = ["render"] # creates some js files, so if it's running, wait for it t
 run = "eslint ."
 ```
 
+Supports the same argument and environment variable syntax as `depends`.
+
 ### `env`
 
 - **Type**: `{ [key]: string | int | bool }`

e2e/tasks/test_task_dep_env

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+
+# Test passing env vars to task dependencies
+
+# Test shell-style env var syntax: "FOO=bar mytask"
+cat <<EOF >mise.toml
+[tasks.show-env]
+run = 'echo "FOO=\$FOO BAZ=\$BAZ"'
+
+[tasks.with-env-string]
+depends = ["FOO=hello show-env"]
+run = 'echo done'
+
+[tasks.with-multiple-env]
+depends = ["FOO=hello BAZ=world show-env"]
+run = 'echo done'
+EOF
+
+assert_contains "mise run with-env-string" "FOO=hello"
+assert_contains "mise run with-multiple-env" "FOO=hello BAZ=world"
+
+# Test structured object syntax: { task = "mytask", env = { FOO = "bar" } }
+cat <<EOF >mise.toml
+[tasks.show-env]
+run = 'echo "FOO=\$FOO BAZ=\$BAZ"'
+
+[tasks.with-env-object]
+depends = [{ task = "show-env", env = { FOO = "hello", BAZ = "world" } }]
+run = 'echo done'
+
+[tasks.with-env-and-args]
+depends = [{ task = "echo-args", env = { FOO = "test" }, args = ["arg1", "arg2"] }]
+run = 'echo done'
+
+[tasks.echo-args]
+run = 'echo "FOO=\$FOO" && echo'
+EOF
+
+assert_contains "mise run with-env-object" "FOO=hello BAZ=world"
+assert_contains "mise run with-env-and-args" "FOO=test"
+# Args are appended to the command line, verify they appear in output
+assert_contains "mise run with-env-and-args" "arg1 arg2"

src/task/mod.rs

@@ -1014,6 +1014,15 @@ fn match_tasks_with_context(
         .map(|t| {
             let mut t = (*t).clone();
             t.args = td.args.clone();
+            // Apply env vars from dependency
+            if !td.env.is_empty() {
+                let env_directives: Vec<EnvDirective> = td
+                    .env
+                    .iter()
+                    .map(|(k, v)| EnvDirective::Val(k.clone(), v.clone(), Default::default()))
+                    .collect();
+                t = t.derive_env(&env_directives);
+            }
             t
         })
         .collect_vec();
@@ -1407,10 +1416,12 @@ mod tests {
                 TaskDep {
                     task: "post1".to_string(),
                     args: vec![],
+                    env: Default::default(),
                 },
                 TaskDep {
                     task: "post2".to_string(),
                     args: vec![],
+                    env: Default::default(),
                 },
             ],
             ..Default::default()
@@ -1422,6 +1433,7 @@ mod tests {
             depends_post: vec![TaskDep {
                 task: "other_post".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1759,6 +1771,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "task_b".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1768,6 +1781,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "task_a".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1795,6 +1809,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "task_b".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1804,6 +1819,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "task_c".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1813,6 +1829,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "task_a".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1842,10 +1859,12 @@ echo "hello world"
                 crate::task::task_dep::TaskDep {
                     task: "task_a".to_string(),
                     args: vec![],
+                    env: Default::default(),
                 },
                 crate::task::task_dep::TaskDep {
                     task: "task_b".to_string(),
                     args: vec![],
+                    env: Default::default(),
                 },
             ],
             ..Default::default()
@@ -1856,6 +1875,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "common".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };
@@ -1865,6 +1885,7 @@ echo "hello world"
             depends: vec![crate::task::task_dep::TaskDep {
                 task: "common".to_string(),
                 args: vec![],
+                env: Default::default(),
             }],
             ..Default::default()
         };