From cd447b5bf9b0548ce8242b0636429a2a51578694 Mon Sep 17 00:00:00 2001
From: Jonah Snider <jonah@jonah.pw>
Date: Wed, 23 Dec 2020 17:54:12 -0800
Subject: [PATCH] fix(volume): fix imperial conversion ratios

---
 src/conversions/volume.ts       | 106 +++++++++++++++-----------------
 test/conversions/volume.test.ts |   8 ++-
 2 files changed, 57 insertions(+), 57 deletions(-)

diff --git a/src/conversions/volume.ts b/src/conversions/volume.ts
index 208c4162..3412d227 100644
--- a/src/conversions/volume.ts
+++ b/src/conversions/volume.ts
@@ -167,64 +167,60 @@ export const volume = {
 	cuin: ratioer(1.6e-1),
 	in3: ratioer(1.6e-1),
 
-	'measurement ton': ratioer(1.2),
-	'measurement tons': ratioer(1.2),
-	MTON: ratioer(1.2),
+	'measurement ton': ratioer(1.133),
+	'measurement tons': ratioer(1.133),
+	MTON: ratioer(1.133),
 	//#endregion
 
 	//#region Imperial
-	'imperial barrel': ratioer(160),
-	'imperial barrels': ratioer(160),
-	'imp bbl': ratioer(160),
-	impbbl: ratioer(160),
-
-	kilderkin: ratioer(160),
-	kilderkins: ratioer(160),
-
-	firkin: ratioer(160),
-	firkins: ratioer(160),
-
-	'imperial bushel': ratioer(160),
-	'imperial bushels': ratioer(160),
-	'imp bsh': ratioer(160),
-	'imp bu': ratioer(160),
-	impbsh: ratioer(160),
-	impbu: ratioer(160),
-
-	'imperial kenning': ratioer(18),
-	'imperial kennings': ratioer(18),
-	kenning: ratioer(18),
-	impkenning: ratioer(18),
-
-	'imperial peck': ratioer(9.1),
-	'imperial pecks': ratioer(9.1),
-	pk: ratioer(9.1),
-	imppk: ratioer(9.1),
-
-	'imperial quart': ratioer(1.1),
-	'imperial quarts': ratioer(1.1),
-	'imp qt': ratioer(1.1),
-	impqt: ratioer(1.1),
-
-	'imperial gallon': ratioer(1 / 219.9692),
-	'imperial gallons': ratioer(1 / 219.9692),
-	'imp gal': ratioer(1 / 219.9692),
-	impgal: ratioer(1 / 219.9692),
-
-	'imperial pint': ratioer(0.57),
-	'imperial pints': ratioer(0.57),
-	'imp pt': ratioer(0.57),
-	imppt: ratioer(0.57),
-
-	gill: ratioer(4.8),
-	gills: ratioer(4.8),
-	gi: ratioer(4.8),
-	impgi: ratioer(4.8),
-
-	'imperial fluid ounce': ratioer(123),
-	'imperial fluid ounces': ratioer(123),
-	'imp fl oz': ratioer(123),
-	impoz: ratioer(123),
+	// https://en.wikipedia.org/wiki/Imperial_units#Volume
+	'imperial barrel': ratioer(0.16),
+	'imperial barrels': ratioer(0.16),
+	'imp bbl': ratioer(0.16),
+	impbbl: ratioer(0.16),
+
+	kilderkin: ratioer(0.08318),
+	kilderkins: ratioer(0.08318),
+
+	firkin: ratioer(0.041),
+	firkins: ratioer(0.041),
+
+	'imperial bushel': ratioer(0.03636872),
+	'imperial bushels': ratioer(0.03636872),
+	'imp bsh': ratioer(0.03636872),
+	'imp bu': ratioer(0.03636872),
+	impbsh: ratioer(0.03636872),
+	impbu: ratioer(0.03636872),
+
+	'imperial peck': ratioer(0.00909218),
+	'imperial pecks': ratioer(0.00909218),
+	pk: ratioer(0.00909218),
+	imppk: ratioer(0.00909218),
+
+	'imperial quart': ratioer(0.0011365225e12),
+	'imperial quarts': ratioer(0.0011365225e12),
+	'imp qt': ratioer(0.0011365225e12),
+	impqt: ratioer(0.0011365225e12),
+
+	'imperial gallon': ratioer(0.00454609e12),
+	'imperial gallons': ratioer(0.00454609e12),
+	'imp gal': ratioer(0.00454609e12),
+	impgal: ratioer(0.00454609e12),
+
+	'imperial pint': ratioer(0.00056826125e12),
+	'imperial pints': ratioer(0.00056826125e12),
+	'imp pt': ratioer(0.00056826125e12),
+	imppt: ratioer(0.00056826125e12),
+
+	gill: ratioer(0.0001420653125e12),
+	gills: ratioer(0.0001420653125e12),
+	gi: ratioer(0.0001420653125e12),
+	impgi: ratioer(0.0001420653125e12),
+
+	'imperial fluid ounce': ratioer(2.84130625e7),
+	'imperial fluid ounces': ratioer(2.84130625e7),
+	'imp fl oz': ratioer(2.84130625e7),
+	impoz: ratioer(2.84130625e7),
 	//#endregion
 
 	//#region US customary liquid measure
diff --git a/test/conversions/volume.test.ts b/test/conversions/volume.test.ts
index 2670db9f..1cb24310 100644
--- a/test/conversions/volume.test.ts
+++ b/test/conversions/volume.test.ts
@@ -13,7 +13,7 @@ describe('volume', () => {
 	convertAssert(1, 'cubic foot', 0.028, 'm3');
 	convertAssert(1, 'board foot', 0.002359737, 'm3');
 	convertAssert(1, 'cubic inch', 16, 'cm3');
-	convertAssert(1, 'measurement ton', 1.2, 'm3');
+	convertAssert(1, 'measurement ton', 1.133, 'm3');
 
 	convertAssert(6.2898, 'oilbbl', 1, 'm3', true);
 	convertAssert(0.0238, 'bbl', 1, 'US gallon', true);
@@ -31,5 +31,9 @@ describe('volume', () => {
 	convertAssert(1, 'US dry quart', 0.946352946, 'liters');
 	convertAssert(1, 'US dry pint', 33.6003125, 'm3');
 
-	convertAssert(219.9692, 'imperial gallons', 1, 'm3');
+	convertAssert(1, 'imperial fluid ounces', 28.4130625, 'ml');
+	convertAssert(1, 'gill', 142.0653125, 'ml');
+	convertAssert(1, 'imperial pints', 568.26125, 'ml');
+	convertAssert(1, 'imperial quarts', 1136.5225, 'ml');
+	convertAssert(1, 'imperial gallons', 4546.09, 'ml');
 });