From c6e7a42b7e455b6e779aa3556a294bfcb2c52f3e Mon Sep 17 00:00:00 2001
From: Alex Auvolat <alex@adnab.me>
Date: Thu, 17 Nov 2022 15:06:42 +0100
Subject: [PATCH] Add 'allow_extra_keys' parameter to dict_of() and
 dict_of_opt()

---
 src/dec/mod.rs | 34 ++++++++++++++++++++++------------
 1 file changed, 22 insertions(+), 12 deletions(-)

diff --git a/src/dec/mod.rs b/src/dec/mod.rs
index 9c1e7d7..2d86e1a 100644
--- a/src/dec/mod.rs
+++ b/src/dec/mod.rs
@@ -262,14 +262,17 @@ impl<'a, 'b> Term<'a, 'b> {
     /// ```
     /// use nettext::dec::decode;
     ///
-    /// let term = decode(b"{ k1 = v1, k2 = v2 }").unwrap();
-    /// let [s1, s2] = term.dict_of([b"k1", b"k2"]).unwrap();
+    /// let term = decode(b"{ k1 = v1, k2 = v2, k3 = v3 }").unwrap();
+    /// let [s1, s2] = term.dict_of([b"k1", b"k2"], true).unwrap();
     /// assert_eq!(s1.str().unwrap(), b"v1");
     /// assert_eq!(s2.str().unwrap(), b"v2");
+    ///
+    /// assert!(term.dict_of([b"k1", b"k2"], false).is_err());
     /// ```
     pub fn dict_of<const N: usize>(
         &self,
         keys: [&'static [u8]; N],
+        allow_extra_keys: bool,
     ) -> Result<[Term<'a, '_>; N], TypeError> {
         match self.0.mkref() {
             AnyTerm::DictRef(_, dict) => {
@@ -279,10 +282,12 @@ impl<'a, 'b> Term<'a, 'b> {
                         return Err(TypeError::MissingKey(debug(k).to_string()));
                     }
                 }
-                // Check that dictionnary contains no extraneous keys
-                for k in dict.keys() {
-                    if !keys.contains(k) {
-                        return Err(TypeError::UnexpectedKey(debug(k).to_string()));
+                if !allow_extra_keys {
+                    // Check that dictionnary contains no extraneous keys
+                    for k in dict.keys() {
+                        if !keys.contains(k) {
+                            return Err(TypeError::UnexpectedKey(debug(k).to_string()));
+                        }
                     }
                 }
                 Ok(keys.map(|k| Term(dict.get(k).unwrap().mkref())))
@@ -299,22 +304,27 @@ impl<'a, 'b> Term<'a, 'b> {
     /// ```
     /// use nettext::dec::decode;
     ///
-    /// let term = decode(b"{ k1 = v1, k2 = v2 }").unwrap();
-    /// let [s1, s2, s3] = term.dict_of_opt([b"k1", b"k2", b"k3"]).unwrap();
+    /// let term = decode(b"{ k1 = v1, k2 = v2, k4 = v4 }").unwrap();
+    /// let [s1, s2, s3] = term.dict_of_opt([b"k1", b"k2", b"k3"], true).unwrap();
     /// assert_eq!(s1.unwrap().str().unwrap(), b"v1");
     /// assert_eq!(s2.unwrap().str().unwrap(), b"v2");
     /// assert!(s3.is_none());
+    ///
+    /// assert!(term.dict_of_opt([b"k1", b"k2", b"k3"], false).is_err());
     /// ```
     pub fn dict_of_opt<const N: usize>(
         &self,
         keys: [&'static [u8]; N],
+        allow_extra_keys: bool,
     ) -> Result<[Option<Term<'a, '_>>; N], TypeError> {
         match self.0.mkref() {
             AnyTerm::DictRef(_, dict) => {
-                // Check that dictionnary contains no extraneous keys
-                for k in dict.keys() {
-                    if !keys.contains(k) {
-                        return Err(TypeError::UnexpectedKey(debug(k).to_string()));
+                if !allow_extra_keys {
+                    // Check that dictionnary contains no extraneous keys
+                    for k in dict.keys() {
+                        if !keys.contains(k) {
+                            return Err(TypeError::UnexpectedKey(debug(k).to_string()));
+                        }
                     }
                 }
                 Ok(keys.map(|k| dict.get(k).map(|x| Term(x.mkref()))))