From e227b997383094d9fa2b01edf9dea0bc421fed4e Mon Sep 17 00:00:00 2001
From: bakaq <bakaq@bakaq.net>
Date: Mon, 19 Aug 2024 18:07:14 -0300
Subject: [PATCH] serde derive for QueryMatch

---
 Cargo.toml                    |  2 +-
 src/machine/lib_machine.rs    |  3 ++-
 src/machine/parsed_results.rs | 41 +++++++++++------------------------
 tests/scryer_lib/main.rs      |  1 -
 4 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index eeb0eaa00..5800da979 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -80,7 +80,7 @@ ego-tree = "0.6.2"
 
 
 serde_json = "1.0.122"
-serde = "1.0.204"
+serde = { version="1.0.204", features = ["derive"] }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 crossterm = { version = "0.28.1", optional = true }
diff --git a/src/machine/lib_machine.rs b/src/machine/lib_machine.rs
index d8431ea0c..ab41ff01d 100644
--- a/src/machine/lib_machine.rs
+++ b/src/machine/lib_machine.rs
@@ -9,6 +9,7 @@ use crate::parser::parser::{Parser, Tokens};
 use crate::read::{write_term_to_heap, TermWriteResult};
 use indexmap::IndexMap;
 
+use super::QueryMatch;
 use super::{
     streams::Stream, Atom, AtomCell, HeapCellValue, HeapCellValueTag, Machine, MachineConfig,
     QueryResolutionLine, QueryResult, Value,
@@ -138,7 +139,7 @@ impl Iterator for QueryState<'_> {
         // choice point, so we should break.
         self.machine.machine_st.backtrack();
 
-        Some(Ok(QueryResolutionLine::Match(bindings)))
+        Some(Ok(QueryResolutionLine::Match(QueryMatch { bindings })))
     }
 }
 
diff --git a/src/machine/parsed_results.rs b/src/machine/parsed_results.rs
index 6f0bfee0a..81bad1f35 100644
--- a/src/machine/parsed_results.rs
+++ b/src/machine/parsed_results.rs
@@ -22,27 +22,16 @@ use serde::Serializer;
 
 pub type QueryResult = Result<QueryResolution, String>;
 
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
 pub struct QueryMatch {
     pub bindings: BTreeMap<String, Value>,
 }
 
-impl Serialize for QueryMatch {
-    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: Serializer,
-    {
-        let mut map = serializer.serialize_map(Some(1))?;
-        map.serialize_entry("bindings", &self.bindings)?;
-        map.end()
-    }
-}
-
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum QueryResolutionLine {
     True,
     False,
-    Match(BTreeMap<String, Value>),
+    Match(QueryMatch),
 }
 
 impl Serialize for QueryResolutionLine {
@@ -53,11 +42,7 @@ impl Serialize for QueryResolutionLine {
         match self {
             QueryResolutionLine::True => serializer.serialize_bool(true),
             QueryResolutionLine::False => serializer.serialize_bool(false),
-            QueryResolutionLine::Match(m) => {
-                let mut map = serializer.serialize_map(Some(1))?;
-                map.serialize_entry("bindings", m)?;
-                map.end()
-            }
+            QueryResolutionLine::Match(m) => m.serialize(serializer),
         }
     }
 }
@@ -142,7 +127,8 @@ impl From<&QueryResolutionLine> for Value {
             QueryResolutionLine::True => Value::Atom("true".into()),
             QueryResolutionLine::False => Value::Atom("false".into()),
             QueryResolutionLine::Match(m) => Value::conjunction(
-                &m.iter()
+                &m.bindings
+                    .iter()
                     .map(|(k, v)| {
                         Value::Structure("=".into(), vec![Value::Var(k.clone()), v.clone()])
                     })
@@ -580,7 +566,7 @@ impl From<Vec<QueryResolutionLine>> for QueryResolution {
         // If there is only one line, and it is an empty match, return false.
         if query_result_lines.len() == 1 {
             if let QueryResolutionLine::Match(m) = query_result_lines[0].clone() {
-                if m.is_empty() {
+                if m.bindings.is_empty() {
                     return QueryResolution::False;
                 }
             }
@@ -600,10 +586,9 @@ impl From<Vec<QueryResolutionLine>> for QueryResolution {
         // If there is at least one match, return all matches.
         let all_matches = query_result_lines
             .into_iter()
-            .filter(|l| matches!(l, QueryResolutionLine::Match(_)))
-            .map(|l| match l {
-                QueryResolutionLine::Match(m) => QueryMatch::from(m),
-                _ => unreachable!(),
+            .filter_map(|l| match l {
+                QueryResolutionLine::Match(m) => Some(m),
+                _ => None,
             })
             .collect::<Vec<_>>();
 
@@ -743,10 +728,10 @@ mod tests {
         let json_value = json!(false);
         assert_eq!(json_value, serde_json::to_value(qrl).unwrap());
 
-        let qrl = QueryResolutionLine::Match(btreemap! {
-            "X".into() => Value::Atom("asdf".into()),
-            "Y".into() => Value::String("fdsa".into()),
-        });
+        let qrl = QueryResolutionLine::Match(QueryMatch::from(btreemap! {
+            "X" => Value::Atom("asdf".into()),
+            "Y" => Value::String("fdsa".into()),
+        }));
         let json_value = json!({
             "bindings": {
                 "X": { "atom": "asdf" },
diff --git a/tests/scryer_lib/main.rs b/tests/scryer_lib/main.rs
index 5bf83de1b..b1ee36bac 100644
--- a/tests/scryer_lib/main.rs
+++ b/tests/scryer_lib/main.rs
@@ -1,5 +1,4 @@
 use scryer_prolog::machine::Machine;
-use serde_json;
 
 #[test]
 #[cfg_attr(miri, ignore = "it takes too long to run")]