ci/test: improve CI jobs and tests

.github/scripts/install_test_binaries.sh

@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+# Installs Solc and Geth binaries
+# Note: intended for use only with CI (x86_64 Ubuntu, MacOS or Windows)
+set -e
+
+GETH_BUILD=${GETH_BUILD:-"1.11.2-73b01f40"}
+
+BIN_DIR=${BIN_DIR:-"$HOME/bin"}
+
+PLATFORM="$(uname -s | awk '{print tolower($0)}')"
+if [ "$PLATFORM" != "linux" ] && [ "$PLATFORM" != "darwin" ]; then
+    EXT=".exe"
+fi
+
+main() {
+    mkdir -p "$BIN_DIR"
+    cd "$BIN_DIR"
+    export PATH="$BIN_DIR:$PATH"
+    if [ "$GITHUB_PATH" ]; then
+        echo "$BIN_DIR" >> "$GITHUB_PATH"
+    fi
+
+    install_geth &
+    g=$!
+    install_solc &
+    wait $g $!
+
+    echo ""
+    echo "Installed Geth:"
+    geth version
+    echo ""
+    echo "Installed Solc:"
+    solc --version
+}
+
+# Installs geth from https://geth.ethereum.org/downloads
+install_geth() {
+    case "$PLATFORM" in
+        linux|darwin)
+            name="geth-$PLATFORM-amd64-$GETH_BUILD"
+            curl -s "https://gethstore.blob.core.windows.net/builds/$name.tar.gz" | tar -xzf -
+            mv -f "$name/geth" ./
+            rm -rf "$name"
+            chmod +x geth
+            ;;
+        *)
+            name="geth-windows-amd64-$GETH_BUILD"
+            zip="$name.zip"
+            curl -so "$zip" "https://gethstore.blob.core.windows.net/builds/$zip"
+            unzip "$zip"
+            mv -f "$name/geth.exe" ./
+            rm -rf "$name" "$zip"
+            ;;
+    esac
+}
+
+# Installs solc from https://binaries.soliditylang.org (https://github.com/ethereum/solc-bin)
+install_solc() {
+    bins_url="https://binaries.soliditylang.org"
+    case "$PLATFORM" in
+        linux)  bins_url+="/linux-amd64";;
+        darwin) bins_url+="/macosx-amd64";;
+        *)      bins_url+="/windows-amd64";;
+    esac
+
+    list=$(curl -s "$bins_url/list.json")
+    # use latest version
+    if [ -z "$SOLC_VERSION" ]; then
+        SOLC_VERSION="$(echo "$list" | jq -r ".latestRelease")"
+    fi
+    bin=$(echo "$list" | jq -r ".releases[\"$SOLC_VERSION\"]")
+
+    if [ "$bin" = "null" ]; then
+        echo "Invalid Solc version: $SOLC_VERSION" 1>&2
+        exit 1
+    fi
+
+    # windows versions <= 0.7.1 use .zip
+    if [[ "$bin" = *.zip ]]; then
+        echo "Cannot install solc <= 0.7.1" 1>&2
+        exit 1
+    fi
+
+    curl -so "$bin" "$bins_url/$bin"
+    mv -f "$bin" "solc$EXT"
+    chmod +x "solc$EXT"
+}
+
+main

.github/workflows/book.yml

@@ -1,16 +1,17 @@
 name: book
+
 on:
   push:
     branches: [master]
     paths:
-      - 'book/**'
-      - 'book.toml'
+      - "book/**"
+      - "book.toml"
 
   pull_request:
     branches: [master]
     paths:
-      - 'book/**'
-      - 'book.toml'
+      - "book/**"
+      - "book.toml"
 
 jobs:
   build: