From 48aa3c83824c3e836b27968e27f2f5cad061d4f5 Mon Sep 17 00:00:00 2001
From: Vladyslav Shtabovenko <dev.vsht@posteo.de>
Date: Thu, 23 Jun 2022 23:55:58 +0200
Subject: [PATCH] Fixed a bug in SpinorChainTranspose (related to issue #177).

---
 FeynCalc/Dirac/SpinorChainTranspose.m |  2 +-
 Tests/Feynman/FCFADiracChainJoin.test | 41 +++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/FeynCalc/Dirac/SpinorChainTranspose.m b/FeynCalc/Dirac/SpinorChainTranspose.m
index d9852c94f..4a04552c9 100755
--- a/FeynCalc/Dirac/SpinorChainTranspose.m
+++ b/FeynCalc/Dirac/SpinorChainTranspose.m
@@ -139,7 +139,7 @@
 		time=AbsoluteTime[];
 		diracObjectsEval = (diracObjects/.dsHead->Identity /. DOT->holdDOT)/. {
 			holdDOT[Spinor[p1_,r1__], b___, Spinor[p2_,r2__]] :>
-			-1*optHead[DOT[Spinor[-p2,r2], FCChargeConjugateTransposed[DOT[b],FCI->True,Explicit->True,DotSimplify->False],Spinor[-p1,r1]]]
+			(-1*optHead[DOT[Spinor[-p2,r2], FCChargeConjugateTransposed[DOT[b]/.holdDOT->DOT,FCI->True,Explicit->True,DotSimplify->False],Spinor[-p1,r1]]])
 		} /. holdDOT -> DOT;
 
 		FCPrint[1, "SpinorChainTranspose: Done transposing spinor chains, timing: ", N[AbsoluteTime[] - time, 4], FCDoControl->sctrVerbose];
diff --git a/Tests/Feynman/FCFADiracChainJoin.test b/Tests/Feynman/FCFADiracChainJoin.test
index a5c1954b4..eb456a170 100644
--- a/Tests/Feynman/FCFADiracChainJoin.test
+++ b/Tests/Feynman/FCFADiracChainJoin.test
@@ -209,6 +209,47 @@ First -> {Spinor[-Momentum[p2, D], mqu, 1]}, FCE -> True]",
 "-Spinor[-Momentum[p2, D], mqu, 1] .
 GAD[Lor3] . (mqu + GSD[-l - p2]) . GAD[LCdummy2] .
 GA[6] . (mqu - GSD[-k - k1 - k2 + l + p2]) . GAD[Lor2] .
+Spinor[Momentum[p1, D], mqu, 1]"},
+{"fcstFCFADiracChainJoin-ID8","FCFADiracChainJoin[
+DiracChain[Spinor[Momentum[k1, D], mle, 1],
+DiracIndex[Dir3]] DiracChain[Spinor[Momentum[k2, D], mle, 1],
+DiracIndex[Dir4]] DiracChain[Spinor[-Momentum[p1, D], mqu, 1],
+DiracIndex[Dir1]] DiracChain[Spinor[-Momentum[p2, D], mqu, 1],
+DiracIndex[Dir2]] DiracChain[DiracGamma[LorentzIndex[Lor2, D], D],
+DiracIndex[Dir5], DiracIndex[Dir1]] DiracChain[
+mqu + DiracGamma[Momentum[-k - k1 - k2 + l + p2, D], D],
+DiracIndex[Dir5], DiracIndex[Dir6]] DiracChain[
+DiracGamma[LorentzIndex[LCdummy1, D], D] . DiracGamma[6],
+DiracIndex[Dir3], DiracIndex[Dir4]] DiracChain[
+DiracGamma[LorentzIndex[LCdummy2, D], D] . DiracGamma[6],
+DiracIndex[Dir2], DiracIndex[Dir6]], FCE -> True]",
+"Spinor[Momentum[k1, D], mle, 1] . GAD[LCdummy1] . GA[6] .
+Spinor[-Momentum[k2, D], mle, 1] Spinor[-Momentum[p1, D], mqu,
+1] . (-GAD[Lor2]) . (mqu +
+	GSD[-k - k1 - k2 + l + p2]) . (-GA[6] . GAD[LCdummy2]) .
+Spinor[Momentum[p2, D], mqu, 1]"},
+{"fcstFCFADiracChainJoin-ID9","FCFADiracChainJoin[
+DiracChain[Spinor[Momentum[k1, D], mle, 1],
+DiracIndex[Dir3]] DiracChain[Spinor[Momentum[k2, D], mle, 1],
+DiracIndex[Dir4]] DiracChain[Spinor[-Momentum[p1, D], mqu, 1],
+DiracIndex[Dir1]] DiracChain[Spinor[-Momentum[p2, D], mqu, 1],
+DiracIndex[Dir2]] DiracChain[DiracGamma[LorentzIndex[Lor2, D], D],
+DiracIndex[Dir5], DiracIndex[Dir1]] DiracChain[
+mqu + DiracGamma[Momentum[-k - k1 - k2 + l + p2, D], D],
+DiracIndex[Dir5], DiracIndex[Dir6]] DiracChain[
+DiracGamma[LorentzIndex[LCdummy1, D], D] . DiracGamma[6],
+DiracIndex[Dir3], DiracIndex[Dir4]] DiracChain[
+DiracGamma[LorentzIndex[LCdummy2, D], D] . DiracGamma[6],
+DiracIndex[Dir2], DiracIndex[Dir6]],
+First -> {Spinor[-Momentum[p2, D], mqu, 1],
+Spinor[Momentum[k1, D], mle, 1]}]",
+"Spinor[Momentum[k1, D], mle, 1] .
+DiracGamma[LorentzIndex[LCdummy1, D], D] . DiracGamma[6] .
+Spinor[-Momentum[k2, D], mle, 1] Spinor[-Momentum[p2, D], mqu, 1] .
+DiracGamma[LorentzIndex[LCdummy2, D], D] .
+DiracGamma[
+6] . (mqu - DiracGamma[Momentum[-k - k1 - k2 + l + p2, D], D]) .
+DiracGamma[LorentzIndex[Lor2, D], D] .
 Spinor[Momentum[p1, D], mqu, 1]"}
 };