fix: inherit env (fixes #76)

Co-Authored-By: eric <[email protected]>

example/tasks.toml

@@ -26,3 +26,26 @@
     done
   """
 
+# these examples illustrate the behavior of env vars in tasks
+#
+# the output of the two following tasks should be the same except for the TESTENV line
+# the first task should be empty, the second should have the TESTENV line with the
+# value "test". Both should include the env vars from the parent process.
+[[task]]
+  id = "noenv"
+  desc = "with no env var provided, the task inherits (sic) the env from the parent process"
+  type = "short"
+  cmd = """
+    echo "TESTENV: $TESTENV"
+    echo "done"
+  """
+
+[[task]]
+  id = "withenv"
+  desc = "providing an env var overwrites the entire env"
+  type = "short"
+  env = { TESTENV = "test" }
+  cmd = """
+    echo "TESTENV: $TESTENV"
+    echo "done"
+  """

pkg/run/integration_test.go

@@ -39,6 +39,13 @@ func TestIntegrationSnapshots(t *testing.T) {
 }
 
 func testExample(t *testing.T, name string) error {
+	// Set up environment variables here so we can validate it's
+	// still accessible to the task's command.
+	if name == "env" {
+		os.Setenv("INHERITED_ENV", "true")
+		defer os.Unsetenv("INHERITED_ENV")
+	}
+
 	dmp := diffmatchpatch.New()
 
 	changedFilePath := filepath.Join("testdata", "snapshots", name, "changed-file")

pkg/run/script_task.go

@@ -164,7 +164,8 @@ func (t *scriptTask) startCmd(stdout io.Writer) error {
 	t.cmd.Dir = t.dir
 	t.cmd.Stdout = stdout
 	t.cmd.Stderr = stdout
-	t.cmd.Env = t.env
+	t.cmd.Env = append(os.Environ(), t.env...)
+
 	if err := t.cmd.Start(); err != nil {
 		return err
 	}

pkg/run/testdata/snapshots/env/out.log

@@ -1,7 +1,8 @@
 ok
 
   test  starting
-        ENVIRONMENT VARIABLE
+        ENV_FROM_TASK: 'some env var value'
+        INHERITED_ENV: 'true'
         exit ok
 
    run  done

pkg/run/testdata/snapshots/env/tasks.toml

@@ -1,6 +1,8 @@
 [[task]]
   id = "test"
   type = "short"
-  cmd = "echo $VALUE"
-  env = { VALUE = "ENVIRONMENT VARIABLE" }
-
+  env = { ENV_FROM_TASK = "some env var value" }
+  cmd = """
+    echo "ENV_FROM_TASK: '$ENV_FROM_TASK'"
+    echo "INHERITED_ENV: '$INHERITED_ENV'"
+  """