feat: Implement terraform module with workspace and version (#644)

6 files changed, 157 insertions, 0 deletions

diff --git a/src/configs/mod.rs b/src/configs/mod.rs
index c840f3bba..dcf0337f4 100644
--- a/src/configs/mod.rs
+++ b/src/configs/mod.rs
@@ -25,6 +25,7 @@ pub mod python;
 pub mod ruby;
 pub mod rust;
 mod starship_root;
+pub mod terraform;
 pub mod time;
 pub mod username;
 
diff --git a/src/configs/starship_root.rs b/src/configs/starship_root.rs
index 293dcb17c..00a647354 100644
--- a/src/configs/starship_root.rs
+++ b/src/configs/starship_root.rs
@@ -36,6 +36,7 @@ impl<'a> RootModuleConfig<'a> for StarshipRootConfig<'a> {
                 "python",
                 "ruby",
                 "rust",
+                "terraform",
                 // ↑ Toolchain version modules ↑
                 "nix_shell",
                 "conda",
diff --git a/src/configs/terraform.rs b/src/configs/terraform.rs
new file mode 100644
index 000000000..3d427e5c4
--- /dev/null
+++ b/src/configs/terraform.rs
@@ -0,0 +1,27 @@
+use crate::config::{ModuleConfig, RootModuleConfig, SegmentConfig};
+
+use ansi_term::{Color, Style};
+use starship_module_config_derive::ModuleConfig;
+
+#[derive(Clone, ModuleConfig)]
+pub struct TerraformConfig<'a> {
+    pub symbol: SegmentConfig<'a>,
+    pub workspace: SegmentConfig<'a>,
+    pub version: SegmentConfig<'a>,
+    pub style: Style,
+    pub disabled: bool,
+    pub show_version: bool,
+}
+
+impl<'a> RootModuleConfig<'a> for TerraformConfig<'a> {
+    fn new() -> Self {
+        TerraformConfig {
+            symbol: SegmentConfig::new("💠 "),
+            workspace: SegmentConfig::default(),
+            version: SegmentConfig::default(),
+            style: Color::Fixed(105).bold(),
+            disabled: false,
+            show_version: false,
+        }
+    }
+}
diff --git a/src/module.rs b/src/module.rs
index 71b25627f..873c2e1ad 100644
--- a/src/module.rs
+++ b/src/module.rs
@@ -36,6 +36,7 @@ pub const ALL_MODULES: &[&str] = &[
     "ruby",
     "rust",
     "php",
+    "terraform",
     "time",
     "username",
 ];
diff --git a/src/modules/mod.rs b/src/modules/mod.rs
index 42951324b..a95ea4fd3 100644
--- a/src/modules/mod.rs
+++ b/src/modules/mod.rs
@@ -25,6 +25,7 @@ mod php;
 mod python;
 mod ruby;
 mod rust;
+mod terraform;
 mod time;
 mod username;
 mod utils;
@@ -68,6 +69,7 @@ pub fn handle<'a>(module: &str, context: &'a Context) -> Option<Module<'a>> {
         "python" => python::module(context),
         "ruby" => ruby::module(context),
         "rust" => rust::module(context),
+        "terraform" => terraform::module(context),
         "time" => time::module(context),
         "username" => username::module(context),
         _ => {
diff --git a/src/modules/terraform.rs b/src/modules/terraform.rs
new file mode 100644
index 000000000..60d0b46c9
--- /dev/null
+++ b/src/modules/terraform.rs
@@ -0,0 +1,125 @@
+use super::{Context, Module, RootModuleConfig};
+
+use crate::configs::terraform::TerraformConfig;
+use crate::utils;
+use std::env;
+use std::io;
+use std::path::PathBuf;
+
+/// Creates a module with the current Terraform version and workspace
+///
+/// Will display the Terraform version and workspace if any of the following criteria are met:
+///     - Current directory contains a `.terraform` directory
+///     - Current directory contains a file with the `.tf` extension
+pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
+    let is_terraform_project = context
+        .try_begin_scan()?
+        .set_folders(&[".terraform"])
+        .set_extensions(&["tf"])
+        .is_match();
+
+    if !is_terraform_project {
+        return None;
+    }
+
+    let mut module = context.new_module("terraform");
+    let config: TerraformConfig = TerraformConfig::try_load(module.config);
+
+    module.set_style(config.style);
+    module.create_segment("symbol", &config.symbol);
+
+    if config.show_version {
+        let terraform_version =
+            format_terraform_version(&utils::exec_cmd("terraform", &["version"])?.stdout.as_str())?;
+        module.create_segment("version", &config.version.with_value(&terraform_version));
+    }
+
+    let terraform_workspace = &get_terraform_workspace(&context.current_dir)?;
+    module.create_segment(
+        "workspace",
+        &config.workspace.with_value(&terraform_workspace),
+    );
+
+    Some(module)
+}
+
+// Determines the currently selected workspace (see https://github.com/hashicorp/terraform/blob/master/command/meta.go for the original implementation)
+fn get_terraform_workspace(cwd: &PathBuf) -> Option<String> {
+    // Workspace can be explicitly overwritten by an env var
+    let workspace_override = env::var("TF_WORKSPACE");
+    if workspace_override.is_ok() {
+        return workspace_override.ok();
+    }
+
+    // Data directory containing current workspace can be overwritten by an env var
+    let datadir = match env::var("TF_DATA_DIR") {
+        Ok(s) => PathBuf::from(s),
+        Err(_) => cwd.join(".terraform"),
+    };
+    match utils::read_file(datadir.join("environment")) {
+        Err(ref e) if e.kind() == io::ErrorKind::NotFound => Some("default".to_string()),
+        Ok(s) => Some(s),
+        _ => None,
+    }
+}
+
+fn format_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
+    Some(
+        version
+            .lines()
+            .next()?
+            .trim_start_matches("Terraform ")
+            .trim()
+            .to_owned()
+            + " ",
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_format_terraform_version_release() {
+        let input = "Terraform v0.12.14";
+        assert_eq!(
+            format_terraform_version(input),
+            Some("v0.12.14 ".to_string())
+        );
+    }
+
+    #[test]
+    fn test_format_terraform_version_prerelease() {
+        let input = "Terraform v0.12.14-rc1";
+        assert_eq!(
+            format_terraform_version(input),
+            Some("v0.12.14-rc1 ".to_string())
+        );
+    }
+
+    #[test]
+    fn test_format_terraform_version_development() {
+        let input = "Terraform v0.12.14-dev (cca89f74)";
+        assert_eq!(
+            format_terraform_version(input),
+            Some("v0.12.14-dev (cca89f74) ".to_string())
+        );
+    }
+
+    #[test]
+    fn test_format_terraform_version_multiline() {
+        let input = "Terraform v0.12.13
+
+Your version of Terraform is out of date! The latest version
+is 0.12.14. You can update by downloading from www.terraform.io/downloads.html
+
+";
+        assert_eq!(
+            format_terraform_version(input),
+            Some("v0.12.13 ".to_string())
+        );
+    }
+}