Add support for Vec<T>

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>

4 files changed, 59 insertions, 1 deletions

diff --git a/src/backend/dialoguer.rs b/src/backend/dialoguer.rs
index 6689250..11d5349 100644
--- a/src/backend/dialoguer.rs
+++ b/src/backend/dialoguer.rs
@@ -1,5 +1,7 @@
 use crate::Backend;
 use crate::ValueBuilder;
+use crate::BuildableValue;
+use crate::CollectionBuilder;
 
 pub struct DialoguerBackend;
 
@@ -80,6 +82,12 @@ impl Backend for DialoguerBackend {
         Box::new(DialoguerValueBuilder::<String>(std::marker::PhantomData))
     }
 
+    fn vec_builder<T>(&self) -> Box<dyn CollectionBuilder<Output = Vec<T>, Error = Self::Error>>
+        where T: 'static + BuildableValue
+    {
+        Box::new(DialoguerVecBuilder::<T>(std::marker::PhantomData))
+    }
+
 }
 
 pub struct DialoguerValueBuilder<T: Sized>(std::marker::PhantomData<T>);
@@ -99,3 +107,26 @@ impl<T> ValueBuilder for DialoguerValueBuilder<T>
 }
 
 
+pub struct DialoguerVecBuilder<T: 'static + BuildableValue>(std::marker::PhantomData<T>);
+impl<T> CollectionBuilder for DialoguerVecBuilder<T>
+    where T: 'static + BuildableValue
+{
+    type Output = Vec<T>;
+    type Error = DialoguerBackendError;
+
+    fn build_collection(&self, value_desc: &str) -> Result<Self::Output, Self::Error> {
+        let mut buf = vec![];
+
+        loop {
+            let v: T = T::builder(DialoguerBackend).build_value(value_desc)?;
+            buf.push(v);
+
+            if !dialoguer::Input::<bool>::new().with_prompt("Another one?").interact_text()? {
+                break
+            }
+        }
+
+        Ok(buf)
+    }
+}
+
diff --git a/src/backend/mod.rs b/src/backend/mod.rs
index dfd77c8..1353a6d 100644
--- a/src/backend/mod.rs
+++ b/src/backend/mod.rs
@@ -1,6 +1,8 @@
 pub mod dialoguer;
 
 use crate::ValueBuilder;
+use crate::BuildableValue;
+use crate::CollectionBuilder;
 
 /// A backend can be used to get builders for specific types
 pub trait Backend {
@@ -23,6 +25,10 @@ pub trait Backend {
     fn f64_builder(&self)    -> Box<dyn ValueBuilder<Output = f64, Error = Self::Error>>;
     fn char_builder(&self)   -> Box<dyn ValueBuilder<Output = char, Error = Self::Error>>;
     fn string_builder(&self) -> Box<dyn ValueBuilder<Output = String, Error = Self::Error>>;
+
+    fn vec_builder<T>(&self) -> Box<dyn CollectionBuilder<Output = Vec<T>, Error = Self::Error>>
+        where T: 'static + BuildableValue
+            ;
 }
 
 
diff --git a/src/buildable.rs b/src/buildable.rs
index 22f6d0a..95382e7 100644
--- a/src/buildable.rs
+++ b/src/buildable.rs
@@ -1,4 +1,5 @@
 use crate::ValueBuilder;
+use crate::CollectionBuilder;
 use crate::Backend;
 
 // A value that can be built interactively, using a Backend
@@ -162,3 +163,23 @@ impl BuildableValue for String {
     }
 }
 
+
+
+pub trait BuildableCollection {
+    fn builder<E, B>(backend: B) -> Box<dyn CollectionBuilder<Output = Self, Error = E>>
+        where E: Sized,
+              B: Backend<Error = E>
+        ;
+}
+
+impl<T> BuildableCollection for Vec<T>
+    where T: 'static + BuildableValue
+{
+    fn builder<E, B>(backend: B) -> Box<dyn CollectionBuilder<Output = Self, Error = E>>
+        where E: Sized,
+              B: Backend<Error = E>
+    {
+        backend.vec_builder::<T>()
+    }
+}
+
diff --git a/src/collection_builder.rs b/src/collection_builder.rs
index 3535ee2..70c1ae3 100644
--- a/src/collection_builder.rs
+++ b/src/collection_builder.rs
@@ -5,6 +5,6 @@ pub trait CollectionBuilder {
     type Output: Sized;
     type Error: Sized;
 
-    fn build_collection(&self) -> Result<Self::Output, Self::Error>;
+    fn build_collection(&self, value_desc: &str) -> Result<Self::Output, Self::Error>;
 }