functora-cfg: configurable key in hash_map, functora-tagged: blanket Deref and Hash impls

Author: functora

rust/functora-cfg/src/lib.rs

@@ -3,6 +3,7 @@ use clap::{Args, FromArgMatches, Subcommand};
 pub use config::ConfigError;
 use config::{Config, Environment, File, Value};
 use serde::{Deserialize, Serialize, de::DeserializeOwned};
+use std::hash::Hash;
 use std::{collections::HashMap, path::Path};
 use toml::Value as TomlValue;
 
@@ -97,7 +98,7 @@ fn toml_to_config(toml: TomlValue) -> Value {
         TomlValue::Table(kv) => Value::from(
             kv.into_iter()
                 .map(|(k, v)| (k, toml_to_config(v)))
-                .collect::<config::Map<String, Value>>(),
+                .collect::<config::Map<_, Value>>(),
         ),
     }
 }
@@ -126,22 +127,26 @@ where
     T: Args,
     U: Subcommand,
 {
-    pub fn vec(self, f: fn(U) -> ReClap<T, U>) -> Vec<T> {
+    pub fn vec(self, rec: fn(U) -> ReClap<T, U>) -> Vec<T> {
         let mut prev = vec![self.prev];
         if let Some(next) = self.next {
-            prev.extend(f(*next).vec(f))
+            prev.extend(rec(*next).vec(rec))
         }
         prev
     }
 
-    pub fn hash_map(
+    pub fn hash_map<K, E>(
         self,
-        f: fn(U) -> ReClap<T, U>,
-    ) -> HashMap<String, T> {
-        self.vec(f)
+        key: fn(usize) -> Result<K, E>,
+        rec: fn(U) -> ReClap<T, U>,
+    ) -> Result<HashMap<K, T>, E>
+    where
+        K: Eq + Hash,
+    {
+        self.vec(rec)
             .into_iter()
             .enumerate()
-            .map(|(k, v)| (k.to_string(), v))
+            .map(|(k, v)| key(k).map(|k| (k, v)))
             .collect()
     }
 }

rust/functora-cfg/tests/integration.rs

@@ -21,16 +21,17 @@ struct Cfg {
 }
 
 impl Cfg {
-    pub fn new(cli: Cli<SubAccount>) -> Self {
+    pub fn new(
+        cli: Cli<SubAccount>,
+    ) -> Result<Self, ConfigError> {
         functora_cfg::Cfg {
             default: &Cli::def(),
             file_path: |cli| cli.toml.as_deref(),
             env_prefix: "FUNCTORA",
             command_line: &cli
-                .fmap(|x| IdClap(x.hash_map())),
+                .try_fmap(|kv| kv.hash_map().map(IdClap))?,
         }
         .eval()
-        .unwrap()
     }
 }
 
@@ -58,9 +59,15 @@ pub enum SubAccount {
 }
 
 impl SubAccount {
-    pub fn hash_map(self) -> HashMap<String, CliAccount> {
+    pub fn hash_map(
+        self,
+    ) -> Result<HashMap<String, CliAccount>, ConfigError>
+    {
         let SubAccount::SubAccount(prev) = self;
-        prev.hash_map(|SubAccount::SubAccount(next)| next)
+        prev.hash_map(
+            |k| Ok(k.to_string()),
+            |SubAccount::SubAccount(next)| next,
+        )
     }
 }
 
@@ -136,7 +143,8 @@ impl Cli<IdClap<HashMap<String, CliAccount>>> {
 #[test]
 #[serial]
 fn defaults() {
-    let lhs = Cfg::new(Cli::parse_from(["functora"]));
+    let lhs =
+        Cfg::new(Cli::parse_from(["functora"])).unwrap();
     let rhs = Cfg {
         host: "127.0.0.1".into(),
         port: 8080,
@@ -170,7 +178,8 @@ fn file_override() {
         "functora",
         "--toml",
         &file.path().to_string_lossy(),
-    ]));
+    ]))
+    .unwrap();
     let rhs = Cfg {
         host: "192.168.1.100".into(),
         port: 8080,
@@ -218,7 +227,8 @@ fn env_override() {
         ],
         || {
             let lhs =
-                Cfg::new(Cli::parse_from(["functora"]));
+                Cfg::new(Cli::parse_from(["functora"]))
+                    .unwrap();
             let rhs = Cfg {
                 host: "10.0.0.1".into(),
                 port: 7070,
@@ -260,7 +270,8 @@ fn cli_override() {
         "pure",
         "--tags",
         "geek",
-    ]));
+    ]))
+    .unwrap();
     let rhs = Cfg {
         host: "127.0.0.1".into(),
         port: 6060,
@@ -331,7 +342,8 @@ fn layered_override() {
                 "vip",
                 "--tags",
                 "beta",
-            ]));
+            ]))
+            .unwrap();
 
             let rhs = Cfg {
                 host: "10.10.10.10".into(),

rust/functora-tagged/src/lib.rs

@@ -2,7 +2,9 @@
 use derive_more::Display;
 use std::error::Error;
 use std::fmt::{Debug, Display};
+use std::hash::{Hash, Hasher};
 use std::marker::PhantomData;
+use std::ops::Deref;
 use std::str::FromStr;
 
 #[derive(Debug)]
@@ -66,6 +68,20 @@ impl<Rep: Display, Tag> Display for Tagged<Rep, Tag> {
     }
 }
 
+impl<Rep: Hash, Tag> Hash for Tagged<Rep, Tag> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.rep().hash(state);
+    }
+}
+
+impl<Rep, Tag> Deref for Tagged<Rep, Tag> {
+    type Target = Rep;
+
+    fn deref(&self) -> &Self::Target {
+        self.rep()
+    }
+}
+
 #[derive(Debug, Display)]
 pub enum ParseError<Rep, Tag>
 where