From 3cdc5c5d3cd4d2907b21e097a91e3f50063281b5 Mon Sep 17 00:00:00 2001
From: Junichi Uekawa <uekawa@google.com>
Date: Tue, 29 Mar 2022 15:32:09 +0900
Subject: [PATCH] argument: Add a key numeric parser.

Sometimes I want numeric key in addition to value.

BUG=b:215297064
TEST=cargo test

Change-Id: I75ae37905d1a27709e2fa694ab01e0ac8ed8596c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3556930
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Commit-Queue: Junichi Uekawa <uekawa@chromium.org>
---
 src/argument.rs | 35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/src/argument.rs b/src/argument.rs
index e659391018..a825822dce 100644
--- a/src/argument.rs
+++ b/src/argument.rs
@@ -445,14 +445,30 @@ impl<'a> KeyValuePair<'a> {
         )))
     }
 
+    fn get_numeric<T>(&self, val: &str) -> Result<T>
+    where
+        T: TryFrom<u64>,
+        <T as TryFrom<u64>>::Error: std::error::Error,
+    {
+        let num = parse_hex_or_decimal(val)?;
+        self.handle_parse_err(T::try_from(num))
+    }
+
     pub fn parse_numeric<T>(&self) -> Result<T>
     where
         T: TryFrom<u64>,
         <T as TryFrom<u64>>::Error: std::error::Error,
     {
         let val = self.value()?;
-        let num = parse_hex_or_decimal(val)?;
-        self.handle_parse_err(T::try_from(num))
+        self.get_numeric(val)
+    }
+
+    pub fn key_numeric<T>(&self) -> Result<T>
+    where
+        T: TryFrom<u64>,
+        <T as TryFrom<u64>>::Error: std::error::Error,
+    {
+        self.get_numeric(self.key())
     }
 
     pub fn parse<T>(&self) -> Result<T>
@@ -726,4 +742,19 @@ mod tests {
         assert!(parse_hex_or_decimal("0xz").is_err());
         assert!(parse_hex_or_decimal("hello world").is_err());
     }
+
+    #[test]
+    fn parse_key_value_options_numeric_key() {
+        let mut opts = parse_key_value_options("test", "0x30,0x100=value,nonnumeric=value", ',');
+        let kv = opts.next().unwrap();
+        assert_eq!(kv.key_numeric::<u32>().unwrap(), 0x30);
+
+        let kv = opts.next().unwrap();
+        assert_eq!(kv.key_numeric::<u32>().unwrap(), 0x100);
+        assert_eq!(kv.value().unwrap(), "value");
+
+        let kv = opts.next().unwrap();
+        assert!(kv.key_numeric::<u32>().is_err());
+        assert_eq!(kv.key(), "nonnumeric");
+    }
 }