Add set -euo pipefail

Add `euo pipefail` to all non-trial shell scripts, note if `x` is
already set we maintain it.

Note we have a pipe in `run_task.sh` that relies on grep not finding
anything i.e., failing, so we cannot use pipefail there. Disable it and
re-enable it after the pipe.

contrib/gen_label_config.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-set -e
+set -euo pipefail
 
 # Generates the label configuration using crates in the repository.
 # The label configuration is appended to the labeler config file.

contrib/release.sh

@@ -3,7 +3,7 @@
 # Check that we can publish crates in their current form if there are changes on top of the tip of
 # master that imply that we are about to do a release.
 
-set -ex
+set -euox pipefail
 
 main () {
     for crate in "internals" "hashes" "bitcoin"; do

contrib/run_task.sh

@@ -1,6 +1,6 @@
 #!/bin/env bash
 
-set -ex
+set -euox pipefail
 
 # Make all cargo invocations verbose.
 export CARGO_TERM_VERBOSE=true
@@ -165,6 +165,10 @@ do_lint() {
 # We should not have any duplicate dependencies. This catches mistakes made upgrading dependencies
 # in one crate and not in another (e.g. upgrade bitcoin_hashes in bitcoin but not in secp).
 do_dup_deps() {
+    # We can't use pipefail because these grep statements fail by design when there is no duplicate,
+    # the shell therefore won't pick up mistakes in your pipe - you are on your own.
+    set +o pipefail
+
     duplicate_dependencies=$(
         # Only show the actual duplicated deps, not their reverse tree, then
         # whitelist the 'syn' crate which is duplicated but it's not our fault.
@@ -182,6 +186,8 @@ do_dup_deps() {
         cargo tree  --target=all --all-features --duplicates
         exit 1
     fi
+
+    set -o pipefail
 }
 
 # Build the docs with a nightly toolchain, in unison with the function

fuzz/cycle.sh

@@ -5,7 +5,8 @@
 #
 # For hfuzz options see https://github.com/google/honggfuzz/blob/master/docs/USAGE.md
 
-set -e
+set -euo pipefail
+
 REPO_DIR=$(git rev-parse --show-toplevel)
 # shellcheck source=./fuzz-util.sh
 source "$REPO_DIR/fuzz/fuzz-util.sh"

fuzz/fuzz.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-set -ex
+set -euox pipefail
 
 REPO_DIR=$(git rev-parse --show-toplevel)
 

fuzz/generate-files.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-set -e
+set -euo pipefail
 
 REPO_DIR=$(git rev-parse --show-toplevel)