From e369ada35a5b021479d1eee7e14bd8f90edc0e77 Mon Sep 17 00:00:00 2001
From: Jake Goulding <jake.goulding@integer32.com>
Date: Fri, 1 May 2020 12:52:00 -0400
Subject: [PATCH] refactor: extract a crate with our custom assertions

There's probably an existing crate that we should use directly, but I
haven't found an exact match yet.
---
 Cargo.lock                       |  5 +++++
 Cargo.toml                       |  6 +++++-
 delorean_test_helpers/Cargo.toml |  9 +++++++++
 delorean_test_helpers/src/lib.rs |  8 ++++++++
 src/encoders/float.rs            |  2 +-
 src/lib.rs                       | 11 -----------
 src/line_parser.rs               |  2 +-
 src/storage/block.rs             |  2 +-
 8 files changed, 30 insertions(+), 15 deletions(-)
 create mode 100644 delorean_test_helpers/Cargo.toml
 create mode 100644 delorean_test_helpers/src/lib.rs

diff --git a/Cargo.lock b/Cargo.lock
index 5d3a0b056e..f37a25cc09 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -373,6 +373,7 @@ dependencies = [
  "criterion 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "croaring 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "csv 1.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "delorean_test_helpers 0.1.0",
  "dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "dotenv 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -400,6 +401,10 @@ dependencies = [
  "tonic-build 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "delorean_test_helpers"
+version = "0.1.0"
+
 [[package]]
 name = "delorean_utilities"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index e71d2b24e7..73bed27cfa 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,7 +6,10 @@ edition = "2018"
 default-run = "delorean"
 
 [workspace]
-members = ["delorean_utilities"]
+members = [
+    "delorean_test_helpers",
+    "delorean_utilities",
+]
 
 [profile.release]
 debug = true
@@ -52,6 +55,7 @@ either = "1.5.3"
 smallvec = "1.2.0"
 
 [dev-dependencies]
+delorean_test_helpers = { path = "delorean_test_helpers" }
 criterion = "0.3"
 assert_cmd = "1.0.0"
 tempfile = "3.1.0"
diff --git a/delorean_test_helpers/Cargo.toml b/delorean_test_helpers/Cargo.toml
new file mode 100644
index 0000000000..e1eb238a7d
--- /dev/null
+++ b/delorean_test_helpers/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "delorean_test_helpers"
+version = "0.1.0"
+authors = ["Paul Dix <paul@pauldix.net>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/delorean_test_helpers/src/lib.rs b/delorean_test_helpers/src/lib.rs
new file mode 100644
index 0000000000..0cc55ef440
--- /dev/null
+++ b/delorean_test_helpers/src/lib.rs
@@ -0,0 +1,8 @@
+use std::f64;
+
+/// A test helper function for asserting floating point numbers are within the machine epsilon
+/// because strict comparison of floating point numbers is incorrect
+pub fn approximately_equal(f1: f64, f2: f64) -> bool {
+    (f1 - f2).abs() < f64::EPSILON
+}
+
diff --git a/src/encoders/float.rs b/src/encoders/float.rs
index df4e6ffadc..f74b95bf21 100644
--- a/src/encoders/float.rs
+++ b/src/encoders/float.rs
@@ -491,7 +491,7 @@ pub fn decode(src: &[u8], dst: &mut Vec<f64>) -> Result<(), Box<dyn Error>> {
 #[allow(clippy::unreadable_literal)]
 #[allow(clippy::excessive_precision)] // TODO: Audit test values for truncation
 mod tests {
-    use crate::tests::approximately_equal;
+    use delorean_test_helpers::approximately_equal;
 
     #[test]
     fn encode_no_values() {
diff --git a/src/lib.rs b/src/lib.rs
index a59cc3303d..85a53ea9a4 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -32,14 +32,3 @@ impl error::Error for Error {
         None
     }
 }
-
-#[cfg(test)]
-pub mod tests {
-    use std::f64;
-
-    /// A test helper function for asserting floating point numbers are within the machine epsilon
-    /// because strict comparison of floating point numbers is incorrect
-    pub fn approximately_equal(f1: f64, f2: f64) -> bool {
-        (f1 - f2).abs() < f64::EPSILON
-    }
-}
diff --git a/src/line_parser.rs b/src/line_parser.rs
index 82ec0d4855..0aac398959 100644
--- a/src/line_parser.rs
+++ b/src/line_parser.rs
@@ -791,7 +791,7 @@ fn map_fail<'a, R1, R2>(
 #[cfg(test)]
 mod test {
     use super::*;
-    use crate::tests::approximately_equal;
+    use delorean_test_helpers::approximately_equal;
 
     type Error = Box<dyn std::error::Error>;
     type Result<T = (), E = Error> = std::result::Result<T, E>;
diff --git a/src/storage/block.rs b/src/storage/block.rs
index 82f667f711..fab00ae954 100644
--- a/src/storage/block.rs
+++ b/src/storage/block.rs
@@ -948,7 +948,7 @@ where
 #[cfg(test)]
 mod test {
     use super::*;
-    use crate::tests::approximately_equal;
+    use delorean_test_helpers::approximately_equal;
     use std::io::Cursor;
 
     #[test]