feat(render): add echo extension

espanso-render/src/extension/echo.rs

@@ -0,0 +1,84 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use crate::{Extension, ExtensionOutput, ExtensionResult, Params, Value};
+use thiserror::Error;
+
+pub struct EchoExtension {}
+
+#[allow(clippy::new_without_default)]
+impl EchoExtension {
+  pub fn new() -> Self {
+    Self {}
+  }
+}
+
+impl Extension for EchoExtension {
+  fn name(&self) -> &str {
+    "echo"
+  }
+
+  fn calculate(
+    &self,
+    _: &crate::Context,
+    _: &crate::Scope,
+    params: &Params,
+  ) -> crate::ExtensionResult {
+    if let Some(Value::String(echo)) = params.get("echo") {
+      ExtensionResult::Success(ExtensionOutput::Single(echo.clone()))
+    } else {
+      ExtensionResult::Error(EchoExtensionError::MissingEchoParameter.into())
+    }
+  }
+}
+
+#[derive(Error, Debug)]
+pub enum EchoExtensionError {
+  #[error("missing 'echo' parameter")]
+  MissingEchoParameter,
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+  use std::iter::FromIterator;
+
+  #[test]
+  fn echo_works_correctly() {
+    let extension = EchoExtension::new();
+
+    let param =
+      Params::from_iter(vec![("echo".to_string(), Value::String("test".to_string()))].into_iter());
+    assert_eq!(
+      extension
+        .calculate(&Default::default(), &Default::default(), &param)
+        .into_success()
+        .unwrap(),
+      ExtensionOutput::Single("test".to_string())
+    );
+  }
+
+  #[test]
+  fn missing_echo_parameter() {
+    let extension = EchoExtension::new();
+
+    let param = Params::new();
+    assert!(matches!(extension.calculate(&Default::default(), &Default::default(), &param), ExtensionResult::Error(_)));
+  }
+}

espanso-render/src/extension/mod.rs

@@ -18,3 +18,4 @@
  */
 
 pub mod date;
+pub mod echo;