From 3a1a5f88473512cd154a33ed233464a5a079d831 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mamy=20Andr=C3=A9-Ratsimbazafy?= <mamy_github@numforge.co>
Date: Thu, 9 Apr 2020 13:58:56 +0200
Subject: [PATCH] More coverage and crosscheck between multiplication,
 squaring, addition, substraction, negation

---
 tests/test_fp12.nim | 69 +++++++++++++++++++++++++++++++++++++++++++++
 tests/test_fp2.nim  | 69 +++++++++++++++++++++++++++++++++++++++++++++
 tests/test_fp6.nim  | 69 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 207 insertions(+)

diff --git a/tests/test_fp12.nim b/tests/test_fp12.nim
index 4494d65..e408eb1 100644
--- a/tests/test_fp12.nim
+++ b/tests/test_fp12.nim
@@ -250,6 +250,75 @@ suite "𝔽p12 = 𝔽p6[√∛(1+𝑖)]":
     test(BLS12_461)
     test(BN462)
 
+  test "Squaring the opposite gives the same result":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let a = rng.random(Fp12[C])
+            var na{.noInit.}: Fp12[C]
+            na.neg(a)
+
+            var rSqr{.noInit.}, rNegSqr{.noInit.}: Fp12[C]
+
+            rSqr.square(a)
+            rNegSqr.square(na)
+
+            check: bool(rSqr == rNegSqr)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
+  test "Multiplication and Addition/Substraction are consistent":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let factor = rand(-30..30)
+
+            let a = rng.random(Fp12[C])
+
+            if factor == 0: continue
+
+            var sum{.noInit.}, one{.noInit.}, f{.noInit.}: Fp12[C]
+            one.setOne()
+
+            if factor < 0:
+              sum.neg(a)
+              f.neg(one)
+              for i in 1 ..< -factor:
+                sum -= a
+                f -= one
+            else:
+              sum = a
+              f = one
+              for i in 1 ..< factor:
+                sum += a
+                f += one
+
+            var r{.noInit.}: Fp12[C]
+
+            r.prod(a, f)
+
+            check: bool(r == sum)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
   test "𝔽p12 = 𝔽p6[√∛(1+𝑖)] addition is associative and commutative":
     proc abelianGroup(curve: static Curve) =
       for _ in 0 ..< Iters:
diff --git a/tests/test_fp2.nim b/tests/test_fp2.nim
index 73bfe72..15303bd 100644
--- a/tests/test_fp2.nim
+++ b/tests/test_fp2.nim
@@ -149,6 +149,75 @@ suite "𝔽p2 = 𝔽p[𝑖] (irreducible polynomial x²+1)":
     test(BLS12_461)
     test(BN462)
 
+  test "Squaring the opposite gives the same result":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let a = rng.random(Fp2[C])
+            var na{.noInit.}: Fp2[C]
+            na.neg(a)
+
+            var rSqr{.noInit.}, rNegSqr{.noInit.}: Fp2[C]
+
+            rSqr.square(a)
+            rNegSqr.square(na)
+
+            check: bool(rSqr == rNegSqr)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
+  test "Multiplication and Addition/Substraction are consistent":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let factor = rand(-30..30)
+
+            let a = rng.random(Fp2[C])
+
+            if factor == 0: continue
+
+            var sum{.noInit.}, one{.noInit.}, f{.noInit.}: Fp2[C]
+            one.setOne()
+
+            if factor < 0:
+              sum.neg(a)
+              f.neg(one)
+              for i in 1 ..< -factor:
+                sum -= a
+                f -= one
+            else:
+              sum = a
+              f = one
+              for i in 1 ..< factor:
+                sum += a
+                f += one
+
+            var r{.noInit.}: Fp2[C]
+
+            r.prod(a, f)
+
+            check: bool(r == sum)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
   test "𝔽p2 = 𝔽p[𝑖] addition is associative and commutative":
     proc abelianGroup(curve: static Curve) =
       for _ in 0 ..< Iters:
diff --git a/tests/test_fp6.nim b/tests/test_fp6.nim
index bafc4e8..8a582ab 100644
--- a/tests/test_fp6.nim
+++ b/tests/test_fp6.nim
@@ -250,6 +250,75 @@ suite "𝔽p6 = 𝔽p2[∛(1+𝑖)] (irreducible polynomial x³ - (1+𝑖))":
     test(BLS12_461)
     test(BN462)
 
+  test "Squaring the opposite gives the same result":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let a = rng.random(Fp6[C])
+            var na{.noInit.}: Fp6[C]
+            na.neg(a)
+
+            var rSqr{.noInit.}, rNegSqr{.noInit.}: Fp6[C]
+
+            rSqr.square(a)
+            rNegSqr.square(na)
+
+            check: bool(rSqr == rNegSqr)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
+  test "Multiplication and Addition/Substraction are consistent":
+    template test(C: static Curve) =
+      block:
+        proc testInstance() =
+          for _ in 0 ..< Iters:
+            let factor = rand(-30..30)
+
+            let a = rng.random(Fp6[C])
+
+            if factor == 0: continue
+
+            var sum{.noInit.}, one{.noInit.}, f{.noInit.}: Fp6[C]
+            one.setOne()
+
+            if factor < 0:
+              sum.neg(a)
+              f.neg(one)
+              for i in 1 ..< -factor:
+                sum -= a
+                f -= one
+            else:
+              sum = a
+              f = one
+              for i in 1 ..< factor:
+                sum += a
+                f += one
+
+            var r{.noInit.}: Fp6[C]
+
+            r.prod(a, f)
+
+            check: bool(r == sum)
+
+        testInstance()
+
+    test(BN254)
+    test(BLS12_377)
+    test(BLS12_381)
+    test(BN446)
+    test(FKM12_447)
+    test(BLS12_461)
+    test(BN462)
+
   test "𝔽p6 = 𝔽p2[∛(1+𝑖)] addition is associative and commutative":
     proc abelianGroup(curve: static Curve) =
       for _ in 0 ..< Iters: