tests: move showgraph() to tinit.sh

Summary:
It's duplicate in all the fbamend tests, and I want to make a change to it. Rather than duplicate it, let's fold it into `tinit`.

In the future, I'll unify this with tglog, printdag, etc.

Reviewed By: quark-zju

Differential Revision: D9323267

fbshipit-source-id: c1db0f2f22ffadbcb8ad3c0bde329798db06f089

tests/test-fb-hgext-fbamend-fold.t

@@ -7,9 +7,6 @@ Set up test environment.
   > [experimental]
   > evolution = createmarkers, allowunstable
   > EOF
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
   $ reset() {
   >   cd ..
   >   rm -rf repo

tests/test-fb-hgext-fbamend-rebase.t

@@ -6,9 +6,6 @@ Set up test environment.
   > [experimental]
   > evolution = createmarkers, allowunstable
   > EOF
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
 
 Test that rebased commits that would cause instability are inhibited.
   $ hg init repo && cd repo

tests/test-fb-hgext-fbamend-restack-auto.t

@@ -9,9 +9,6 @@
   >   hg add "$1"
   >   hg ci -m "add $1"
   > }
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
 
 Test invalid value for amend.autorestack
   $ newrepo

tests/test-fb-hgext-fbamend-restack-divergence.t

@@ -8,9 +8,6 @@
   >   hg add "$1"
   >   hg ci -m "add $1"
   > }
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
 
 Test situation with divergence. Restack should rebase unstable children
 onto the newest successor of their parent.

tests/test-fb-hgext-fbamend-restack-multidest.t

@@ -8,9 +8,6 @@
   >   hg add "$1"
   >   hg ci -m "add $1"
   > }
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
 
 Restack does topological sort and only rebases "D" once:
 

tests/test-fb-hgext-fbamend-restack.t

@@ -10,9 +10,6 @@ Set up test environment.
   >   hg add "$1"
   >   hg ci -m "add $1"
   > }
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
   $ hg init restack && cd restack
 
 Note: Repositories populated by `hg debugbuilddag` don't seem to

tests/test-fb-hgext-fbamend-split.t

@@ -24,9 +24,6 @@ Set up test environment.
   >   hg init repo
   >   cd repo
   > }
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
 
 Initialize repo.
   $ hg init repo && cd repo

tests/test-fb-hgext-fold-undo.t

@@ -9,9 +9,6 @@ This test confirms cacheinvalidation in hg fold.
   > [experimental]
   > evolution = createmarkers, allowunstable
   > EOF
-  $ showgraph() {
-  >   hg log --graph -T "{rev} {desc|firstline}" | sed \$d
-  > }
   $ reset() {
   >   cd ..
   >   rm -rf repo

tests/tinit.sh

@@ -47,3 +47,7 @@ drawdag() {
 setconfig() {
   python "$RUNTESTDIR/setconfig.py" "$@"
 }
+
+showgraph() {
+  hg log --graph -T "{rev} {desc|firstline}" | sed \$d
+}