fix: Improve type-safety for Step

workspace/gh-workflow/src/cargo.rs

@@ -1,7 +1,7 @@
 use derive_setters::Setters;
 
 use crate::toolchain::Version;
-use crate::StepValue;
+use crate::{Run, Step};
 
 #[derive(Setters)]
 #[setters(strip_option, into)]
@@ -39,7 +39,7 @@ impl Cargo {
     }
 }
 
-impl From<Cargo> for StepValue {
+impl From<Cargo> for Step<Run> {
     fn from(value: Cargo) -> Self {
         let mut command = vec!["cargo".to_string()];
 
@@ -55,7 +55,7 @@ impl From<Cargo> for StepValue {
             }
         }
 
-        let mut step = StepValue::run(command.join(" "));
+        let mut step = Step::run(command.join(" "));
 
         if let Some(id) = value.id {
             step = step.id(id);

workspace/gh-workflow/src/event.rs

@@ -15,7 +15,7 @@ pub struct Event {
     // TODO: add all more events
 }
 
-#[derive(Debug, Setters, Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
+#[derive(Debug, Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
 #[serde(rename_all = "snake_case")]
 pub struct Push {
     branches: Vec<String>,
@@ -26,6 +26,10 @@ impl Push {
         self.branches.push(branch.to_string());
         self
     }
+
+    pub fn branches(self, branches: Vec<String>) -> Self {
+        Push { branches }
+    }
 }
 
 impl From<Push> for Event {

workspace/gh-workflow/src/lib.rs

@@ -10,3 +10,7 @@ pub use cargo::*;
 pub use event::*;
 pub use rust_flag::*;
 pub use workflow::*;
+
+mod private {
+    pub trait Sealed {}
+}

workspace/gh-workflow/src/toolchain.rs

@@ -4,7 +4,7 @@ use std::fmt::{Display, Formatter};
 
 use derive_setters::Setters;
 
-use crate::{Input, RustFlags, StepValue};
+use crate::{Input, RustFlags, Step, Use};
 
 #[derive(Clone)]
 pub enum Version {
@@ -191,10 +191,10 @@ impl Toolchain {
     }
 }
 
-impl From<Toolchain> for StepValue {
+impl From<Toolchain> for Step<Use> {
     fn from(value: Toolchain) -> Self {
-        let mut step = StepValue::uses("actions-rust-lang", "setup-rust-toolchain", 1)
-            .name("Setup Rust Toolchain");
+        let mut step =
+            Step::uses("actions-rust-lang", "setup-rust-toolchain", 1).name("Setup Rust Toolchain");
 
         let toolchain = value
             .toolchain

workspace/gh-workflow/src/workflow.rs

@@ -11,7 +11,7 @@ use serde_json::Value;
 
 use crate::error::Result;
 use crate::generate::Generate;
-use crate::Event;
+use crate::{private, Event};
 
 #[derive(Debug, Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
 #[serde(transparent)]
@@ -175,15 +175,17 @@ impl Job {
         }
     }
 
-    pub fn add_step<S: Into<StepValue>>(mut self, step: S) -> Self {
+    pub fn add_step<S: Into<Step<T>>, T: StepType>(mut self, step: S) -> Self {
         let mut steps = self.steps.unwrap_or_default();
-        steps.push(step.into());
+        let step: Step<T> = step.into();
+        let step: StepValue = T::to_value(step);
+        steps.push(step);
         self.steps = Some(steps);
         self
     }
 }
 
-#[derive(Debug, Setters, Serialize, Deserialize, Clone, PartialEq, Eq)]
+#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq)]
 #[serde(transparent)]
 pub struct Step<A> {
     value: StepValue,
@@ -209,6 +211,26 @@ pub struct Use;
 #[derive(Debug, Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
 pub struct Run;
 
+/// A trait to convert Step<Run> and Step<Use> to StepValue.
+pub trait StepType: Sized + private::Sealed {
+    fn to_value(s: Step<Self>) -> StepValue;
+}
+
+impl private::Sealed for Run {}
+impl private::Sealed for Use {}
+
+impl StepType for Run {
+    fn to_value(s: Step<Self>) -> StepValue {
+        s.into()
+    }
+}
+
+impl StepType for Use {
+    fn to_value(s: Step<Self>) -> StepValue {
+        s.into()
+    }
+}
+
 #[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq, Default)]
 #[serde(transparent)]
 pub struct Env(IndexMap<String, Value>);
@@ -297,18 +319,6 @@ impl StepValue {
             ..Default::default()
         }
     }
-
-    pub fn add_with<I: Into<Input>>(mut self, new_with: I) -> Self {
-        let mut with = self.with.unwrap_or_default();
-        with.merge(new_with.into());
-        if with.0.is_empty() {
-            self.with = None;
-        } else {
-            self.with = Some(with);
-        }
-
-        self
-    }
 }
 
 impl Step<Run> {
@@ -325,9 +335,24 @@ impl Step<Use> {
         }
     }
 
+    /// Creates a step pointing to the default Github's Checkout Action
+    /// See: <https://github.com/actions/checkout>
     pub fn checkout() -> Step<Use> {
         Step::uses("actions", "checkout", 4).name("Checkout Code")
     }
+
+    /// Add a new input to the step.
+    pub fn add_with<I: Into<Input>>(mut self, new_with: I) -> Self {
+        let mut with = self.value.with.unwrap_or_default();
+        with.merge(new_with.into());
+        if with.0.is_empty() {
+            self.value.with = None;
+        } else {
+            self.value.with = Some(with);
+        }
+
+        self
+    }
 }
 
 impl<S1: ToString, S2: ToString> From<(S1, S2)> for Input {