From d4a55ccb17a162b6c105b74ecb85a575f3d1634d Mon Sep 17 00:00:00 2001
From: Savanni D'Gerinel <savanni@luminescent-dreams.com>
Date: Wed, 24 May 2023 10:34:25 -0400
Subject: [PATCH] Implement tests for Timestamp

---
 emseries/src/date_time_tz.rs | 11 ++++++++---
 emseries/src/types.rs        | 33 ++++++++++++++++++++++++++++++---
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/emseries/src/date_time_tz.rs b/emseries/src/date_time_tz.rs
index 287e2e1..447f4de 100644
--- a/emseries/src/date_time_tz.rs
+++ b/emseries/src/date_time_tz.rs
@@ -17,7 +17,7 @@ use chrono::SecondsFormat;
 use chrono_tz::Etc::UTC;
 use serde::de::{self, Deserialize, Deserializer, Visitor};
 use serde::ser::{Serialize, Serializer};
-use std::fmt;
+use std::{fmt, str::FromStr};
 
 /// This is a wrapper around date time objects, using timezones from the chroon-tz database and
 /// providing string representation and parsing of the form "<RFC3339> <Timezone Name>", i.e.,
@@ -54,8 +54,12 @@ impl DateTimeTz {
             )
         }
     }
+}
 
-    pub fn from_str(s: &str) -> Result<DateTimeTz, chrono::ParseError> {
+impl std::str::FromStr for DateTimeTz {
+    type Err = chrono::ParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
         let v: Vec<&str> = s.split_terminator(" ").collect();
         if v.len() == 2 {
             let tz = v[1].parse::<chrono_tz::Tz>().unwrap();
@@ -98,11 +102,12 @@ impl<'de> Deserialize<'de> for DateTimeTz {
 mod test {
     extern crate serde_json;
 
+    use super::*;
     use chrono::TimeZone;
     use chrono_tz::America::Phoenix;
     use chrono_tz::Etc::UTC;
     use chrono_tz::US::{Arizona, Central};
-    use date_time_tz::DateTimeTz;
+    use std::str::FromStr;
 
     #[test]
     fn it_creates_timestamp_with_z() {
diff --git a/emseries/src/types.rs b/emseries/src/types.rs
index 12a841b..af41630 100644
--- a/emseries/src/types.rs
+++ b/emseries/src/types.rs
@@ -44,11 +44,21 @@ pub enum EmseriesWriteError {
     JSONWriteError(serde_json::error::Error),
 }
 
-enum TimestampFormat {
+#[derive(Debug, Clone, PartialEq)]
+enum Timestamp {
     DateTimeTz(DateTimeTz),
     Date(NaiveDate),
 }
 
+impl str::FromStr for Timestamp {
+    type Err = chrono::ParseError;
+    fn from_str(line: &str) -> Result<Self, Self::Err> {
+        DateTimeTz::from_str(line)
+            .map(|dtz| Timestamp::DateTimeTz(dtz))
+            .or(NaiveDate::from_str(line).map(|d| Timestamp::Date(d)))
+    }
+}
+
 /// Any element to be put into the database needs to be Recordable. This is the common API that
 /// will aid in searching and later in indexing records.
 pub trait Recordable {
@@ -116,6 +126,7 @@ mod test {
     extern crate serde_json;
 
     use self::dimensioned::si::{Kilogram, KG};
+    use super::*;
     use super::{Record, Recordable};
     use chrono::TimeZone;
     use chrono_tz::Etc::UTC;
@@ -141,10 +152,26 @@ mod test {
         }
     }
 
+    #[test]
+    fn timestamp_parses_datetimetz_without_timezone() {
+        assert_eq!(
+            "2003-11-10T06:00:00Z".parse::<Timestamp>().unwrap(),
+            Timestamp::DateTimeTz(DateTimeTz(UTC.ymd(2003, 11, 10).and_hms(6, 0, 0))),
+        );
+    }
+
+    #[test]
+    fn timestamp_parses_date() {
+        assert_eq!(
+            "2023-11-10".parse::<Timestamp>().unwrap(),
+            Timestamp::Date(NaiveDate::from_ymd_opt(2023, 11, 10).unwrap())
+        );
+    }
+
     const WEIGHT_ENTRY: &str = "{\"data\":{\"weight\":77.79109,\"date\":\"2003-11-10T06:00:00.000000000000Z\"},\"id\":\"3330c5b0-783f-4919-b2c4-8169c38f65ff\"}";
 
     #[test]
-    pub fn legacy_deserialization() {
+    fn legacy_deserialization() {
         let rec: Record<WeightRecord> = WEIGHT_ENTRY
             .parse()
             .expect("should successfully parse the record");
@@ -162,7 +189,7 @@ mod test {
     }
 
     #[test]
-    pub fn serialization_output() {
+    fn serialization_output() {
         let rec = WeightRecord {
             date: DateTimeTz(UTC.ymd(2003, 11, 10).and_hms(6, 0, 0)),
             weight: Weight(77.0 * KG),