feat(terraform): support opentofu for terraform version detection (#6910)

Support OpenTofu

This is a revitalization of https://github.com/starship/starship/pull/6072

Co-authored-by: Bojan Rajkovic <brajkovic@coderinserepeat.com>

.github/config-schema.json

@@ -1618,6 +1618,16 @@
         "symbol": "💠 ",
         "style": "bold 105",
         "disabled": false,
+        "commands": [
+          [
+            "terraform",
+            "version"
+          ],
+          [
+            "tofu",
+            "version"
+          ]
+        ],
         "detect_extensions": [
           "tf",
           "tfplan",

docs/config/README.md

@@ -4600,9 +4600,10 @@ format = 'via [🏎  $version](red bold)'
 ## Terraform
 
 The `terraform` module shows the currently selected [Terraform workspace](https://www.terraform.io/docs/language/state/workspaces.html) and version.
+It supports both Hashicorp Terraform and OpenTofu for version detection.
 
 > [!TIP]
-> By default the Terraform version is not shown, since this is slow for current versions of Terraform when a lot of plugins are in use.
+> By default the Terraform/OpenTofu version is not shown, since this is slow for current versions when a lot of plugins are in use.
 > If you still want to enable it, [follow the example shown below](#with-terraform-version).
 
 By default the module will be shown if any of the following conditions are met:
@@ -4612,16 +4613,17 @@ By default the module will be shown if any of the following conditions are met:
 
 ### Options
 
-| Option              | Default                              | Description                                                               |
-| ------------------- | ------------------------------------ | ------------------------------------------------------------------------- |
-| `format`            | `'via [$symbol$workspace]($style) '` | The format string for the module.                                         |
-| `version_format`    | `'v${raw}'`                          | The version format. Available vars are `raw`, `major`, `minor`, & `patch` |
-| `symbol`            | `'💠'`                               | A format string shown before the terraform workspace.                     |
-| `detect_extensions` | `['tf', 'tfplan', 'tfstate']`        | Which extensions should trigger this module.                              |
-| `detect_files`      | `[]`                                 | Which filenames should trigger this module.                               |
-| `detect_folders`    | `['.terraform']`                     | Which folders should trigger this module.                                 |
-| `style`             | `'bold 105'`                         | The style for the module.                                                 |
-| `disabled`          | `false`                              | Disables the `terraform` module.                                          |
+| Option              | Default                                                 | Description                                                               |
+| ------------------- | ------------------------------------------------------- | ------------------------------------------------------------------------- |
+| `format`            | `'via [$symbol$workspace]($style) '`                    | The format string for the module.                                         |
+| `version_format`    | `'v${raw}'`                                             | The version format. Available vars are `raw`, `major`, `minor`, & `patch` |
+| `symbol`            | `'💠'`                                                  | A format string shown before the terraform workspace.                     |
+| `detect_extensions` | `['tf', 'tfplan', 'tfstate']`                           | Which extensions should trigger this module.                              |
+| `detect_files`      | `[]`                                                    | Which filenames should trigger this module.                               |
+| `detect_folders`    | `['.terraform']`                                        | Which folders should trigger this module.                                 |
+| `style`             | `'bold 105'`                                            | The style for the module.                                                 |
+| `disabled`          | `false`                                                 | Disables the `terraform` module.                                          |
+| `commands`          | `[ [ 'terraform', 'version' ], [ 'tofu', 'version' ] ]` | How to detect what the Terraform version is.                              |
 
 ### Variables
 
@@ -4642,7 +4644,7 @@ By default the module will be shown if any of the following conditions are met:
 # ~/.config/starship.toml
 
 [terraform]
-format = '[🏎💨 $version$workspace]($style) '
+format = 'via [$symbol$version $workspace]($style) '
 ```
 
 #### Without Terraform version
@@ -4651,7 +4653,7 @@ format = '[🏎💨 $version$workspace]($style) '
 # ~/.config/starship.toml
 
 [terraform]
-format = '[🏎💨 $workspace]($style) '
+format = 'via [$symbol$workspace]($style) '
 ```
 
 ## Time

src/configs/terraform.rs

@@ -16,6 +16,7 @@ pub struct TerraformConfig<'a> {
     pub detect_extensions: Vec<&'a str>,
     pub detect_files: Vec<&'a str>,
     pub detect_folders: Vec<&'a str>,
+    pub commands: Vec<Vec<&'a str>>,
 }
 
 impl Default for TerraformConfig<'_> {
@@ -29,6 +30,12 @@ impl Default for TerraformConfig<'_> {
             detect_extensions: vec!["tf", "tfplan", "tfstate"],
             detect_files: vec![],
             detect_folders: vec![".terraform"],
+            commands: vec![
+                // terraform is usually `terraform`
+                vec!["terraform", "version"],
+                // but for opentofu users, it'll be `tofu`
+                vec!["tofu", "version"],
+            ],
         }
     }
 }

src/modules/terraform.rs

@@ -37,7 +37,10 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
             .map(|variable| match variable {
                 "version" => {
                     let terraform_version = parse_terraform_version(
-                        context.exec_cmd("terraform", &["version"])?.stdout.as_str(),
+                        context
+                            .exec_cmds_return_first(config.commands.clone())?
+                            .stdout
+                            .as_str(),
                     )?;
                     VersionFormatter::format_module_version(
                         module.get_name(),
@@ -84,13 +87,15 @@ fn get_terraform_workspace(context: &Context) -> Option<String> {
 }
 
 fn parse_terraform_version(version: &str) -> Option<String> {
-    // `terraform version` output looks like this
-    // Terraform v0.12.14
-    // With potential extra output if it detects you are not running the latest version
+    // `terraform version` or `tofu version` output looks like this
+    //   Terraform v0.12.14/OpenTofu v1.7.2
+    // with potential extra output if it detects you are not running the latest version
+
     let version = version
         .lines()
         .next()?
         .trim_start_matches("Terraform ")
+        .trim_start_matches("OpenTofu ")
         .trim()
         .trim_start_matches('v');
 
@@ -111,6 +116,22 @@ mod tests {
         assert_eq!(parse_terraform_version(input), Some("0.12.14".to_string()));
     }
 
+    #[test]
+    fn test_parse_opentofu_version_release() {
+        let input = "OpenTofu v1.7.2";
+        assert_eq!(parse_terraform_version(input), Some("1.7.2".to_string()));
+    }
+
+    #[test]
+    fn test_parse_opentofu_version_multiline() {
+        let input = "OpenTofu v1.7.2
+on darwin_arm64
++ provider registry.opentofu.org/hashicorp/helm v2.14.0
++ provider registry.opentofu.org/hashicorp/kubernetes v2.31.0
+";
+        assert_eq!(parse_terraform_version(input), Some("1.7.2".to_string()));
+    }
+
     #[test]
     fn test_parse_terraform_version_prerelease() {
         let input = "Terraform v0.12.14-rc1";
@@ -120,6 +141,15 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_parse_opentofu_version_prerelease() {
+        let input = "OpenTofu v1.8.0-alpha1";
+        assert_eq!(
+            parse_terraform_version(input),
+            Some("1.8.0-alpha1".to_string())
+        )
+    }
+
     #[test]
     fn test_parse_terraform_version_development() {
         let input = "Terraform v0.12.14-dev (cca89f74)";