bindings: Parse polyglot bindings

Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>

1 files changed, 50 insertions, 12 deletions

diff --git a/src/bindings.rs b/src/bindings.rs
index 5b8d013..9282155 100644
--- a/src/bindings.rs
+++ b/src/bindings.rs
@@ -10,6 +10,7 @@ use serde_aux::prelude::*;
 
 use std::collections::HashMap;
 use std::fmt::Debug;
+use std::ops::Deref;
 use std::path::Path;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -206,8 +207,8 @@ impl Binding {
     }
 
     /// Retrieve a particular implementation by name
-    pub fn step_impl(&self, template: &str) -> Option<Arc<BindingImpl>> {
-        self.impls.get(template).cloned()
+    pub fn step_impl(&self, _template: &str) -> Option<Arc<BindingImpl>> {
+        self.impls.values().next().cloned()
     }
 
     /// Return the compiled regular expression for the pattern of the
@@ -399,12 +400,33 @@ impl Default for Bindings {
 }
 
 #[derive(Debug, Deserialize)]
+struct ParsedImpl {
+    function: String,
+    cleanup: Option<String>,
+}
+
+#[derive(Debug, Deserialize)]
+#[serde(transparent)]
+struct ParsedImplWrapper {
+    #[serde(deserialize_with = "deserialize_struct_case_insensitive")]
+    pimpl: ParsedImpl,
+}
+
+impl Deref for ParsedImplWrapper {
+    type Target = ParsedImpl;
+
+    fn deref(&self) -> &Self::Target {
+        &self.pimpl
+    }
+}
+
+#[derive(Debug, Deserialize)]
 struct ParsedBinding {
     given: Option<String>,
     when: Option<String>,
     then: Option<String>,
-    function: String,
-    cleanup: Option<String>,
+    #[serde(default, rename = "impl")]
+    impls: HashMap<String, ParsedImplWrapper>,
     regex: Option<bool>,
     #[serde(default)]
     case_sensitive: bool,
@@ -549,7 +571,9 @@ fn from_hashmap(parsed: &ParsedBinding) -> Result<Binding> {
 
     let mut ret = Binding::new(kind, &pattern, parsed.case_sensitive, types)?;
     event!(Level::TRACE, "Binding parsed OK");
-    ret.add_impl("", &parsed.function, parsed.cleanup.as_deref());
+    for (template, pimpl) in &parsed.impls {
+        ret.add_impl(template, &pimpl.function, pimpl.cleanup.as_deref());
+    }
 
     Ok(ret)
 }
@@ -589,16 +613,26 @@ mod test_bindings {
     fn adds_from_yaml() {
         let yaml = "
 - GIVEN: I am Tomjon
-  function: set_name
+  impl:
+    python:
+      function: set_name
 - when: I declare myself king
-  Function: declare_king
+  impl:
+    python:
+      Function: declare_king
 - tHEn: there is applause
-  function: check_for_applause
+  impl:
+    python:
+      function: check_for_applause
 - given: you are alice
-  function: other_name
+  impl:
+    python:
+      function: other_name
   case_sensitive: true
 - then: the total is {total}
-  function: check_total
+  impl:
+    python:
+      function: check_total
   types:
     total: word
 ";
@@ -619,7 +653,9 @@ mod test_bindings {
         let yaml = "
 - Given: I am Tomjon
   wheN: I am indeed Tomjon
-  FUNCTION: set_name
+  impl:
+    python:
+      FUNCTION: set_name
 ";
         match Bindings::new().add_from_yaml(yaml) {
             Ok(_) => unreachable!(),
@@ -632,7 +668,9 @@ mod test_bindings {
     fn typemap_must_match_pattern() {
         let yaml = "
 - then: you are {age:word} years old
-  function: check_age
+  impl:
+    python:
+      function: check_age
   types:
     age: number
 ";