add .gitattributes to ignore changes in Manifest.toml

.gitattributes

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+Manifest.toml linguist-generated=true

test/rules.jl

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+module rules
+
+using Test, Diffractor, ChainRulesCore
+using Diffractor: var"'"
+
+# invalidation for rrule
+rrule_demo(x) = sin(x)
+function rrule_demo_pullback(x)
+    return function (Δx)
+        return NoTangent(), Δx*cos(x)
+    end
+end
+function ChainRulesCore.rrule(::typeof(rrule_demo), x)
+    return rrule_demo(x), rrule_demo_pullback(x)
+end
+@test cos(42) == rrule_demo'(42)
+function rrule_demo_pullback(x)
+    return function (Δx)
+        return NoTangent(), Δx*sin(x)
+    end
+end
+@test sin(42) == rrule_demo'(42)
+
+# invalidation for frule
+frule_demo(x) = sin(x)
+function frule_demo_impl(Δx, x)
+    sinx, cosx = sincos(x)
+    return (sinx, sinx * Δx)
+end
+function ChainRulesCore.frule((_, Δx), ::typeof(frule_demo), x)
+    return frule_demo_impl(Δx, x)
+end
+@test cos(42) == frule_demo'(42)
+function frule_demo_impl(Δx, x)
+    sinx, cosx = sincos(x)
+    return (sinx, sinx * Δx)
+end
+@test sin(42) == frule_demo'(42)
+
+end # module rules