Merge #480: Run shellcheck on the ci script

1bbc1e7 Explicitly set RUSTDOCFLAGS (Tobin C. Harding)
bf95a02 Use the STD_FEATURES list (Tobin C. Harding)
c8dc4b6 Remove TOOLCHAIN (Tobin C. Harding)
d14cccb Add alloc to features (Tobin C. Harding)
1194591 Use set -ex instead of /bin/sh -ex (Tobin C. Harding)

Pull request description:

  The first 3 patches are preparatory cleanup in line with what has been done lately in `rust-bitcoin`. The last two are real bugs found by `shellcheck`.

  Props to dpc for putting me on to `shellcheck`.

ACKs for top commit:
  apoelstra:
    ACK 1bbc1e7

Tree-SHA512: 9eac1e8a19f2fb7d7413c8b76d8b8c14c1ec88e523565b4b907ef595496e0e59f9ae33896024211990cc59bf82bb36cba09dabeb28605e50d5db075bbe39457a

Author: apoelstra

contrib/test.sh

@@ -1,19 +1,12 @@
-#!/bin/sh -ex
+#!/bin/sh
 
-set -e
+set -ex
 
-# TODO: Add "alloc" once we bump MSRV to past 1.29
-FEATURES="bitcoin_hashes global-context lowmemory rand recovery serde std"
+FEATURES="bitcoin_hashes global-context lowmemory rand recovery serde std alloc"
 # These features are typically enabled along with the 'std' feature, so we test
 # them together with 'std'.
 STD_FEATURES="rand-std bitcoin-hashes-std"
 
-# Use toolchain if explicitly specified
-if [ -n "$TOOLCHAIN" ]
-then
-    alias cargo="cargo +$TOOLCHAIN"
-fi
-
 cargo --version
 rustc --version
 
@@ -53,9 +46,10 @@ if [ "$DO_FEATURE_MATRIX" = true ]; then
         cargo test --all --no-default-features --features="std,$feature"
     done
     # Other combos 
-    RUSTFLAGS='--cfg=fuzzing' RUSTDOCFLAGS=$RUSTFLAGS cargo test --all
-    RUSTFLAGS='--cfg=fuzzing' RUSTDOCFLAGS=$RUSTFLAGS cargo test --all --features="$FEATURES"
+    RUSTFLAGS='--cfg=fuzzing' RUSTDOCFLAGS='--cfg=fuzzing' cargo test --all
+    RUSTFLAGS='--cfg=fuzzing' RUSTDOCFLAGS='--cfg=fuzzing' cargo test --all --features="$FEATURES"
     cargo test --all --features="rand serde"
+    cargo test --features="$STD_FEATURES"
 
     if [ "$NIGHTLY" = true ]; then
         cargo test --all --all-features