dapp: remappings: add flag for legacy compat

src/dapp-tests/integration/tests.sh

@@ -60,6 +60,17 @@ dapp_remappings() {
 
 dapp_remappings
 
+# tests dapp remappings on a large legacy project with many implicit imports
+dapp_remappings_compat() {
+    REV="bc6d7657f0f5190f65051543199e1b47bf29932b"
+    TMPDIR=$(mktemp -d)
+    git clone https://github.com/dapp-org/tinlake-tests "$TMPDIR"
+    export DAPP_ALLOW_IMPLICIT_IMPORTS=yes
+    (cd "$TMPDIR" && git checkout "$REV" && dapp update && dapp --use solc:0.7.6 build)
+}
+
+dapp_remappings_compat
+
 test_hevm_symbolic() {
     solc --bin-runtime -o . --overwrite factor.sol
     # should find counterexample

src/dapp/default.nix

@@ -1,6 +1,7 @@
 { lib, stdenv, fetchFromGitHub, makeWrapper, glibcLocales
-, coreutils, git, gnused, gnumake, hevm, jshon, jq, nix
-, nodejs, perl, python3, seth, shellcheck, solc, tre, dapptoolsSrc }:
+, coreutils, findutils, ripgrep, git, gnused, gnumake, hevm
+, jshon, jq, nix, nodejs, perl, python3, seth, shellcheck, solc
+, tre, dapptoolsSrc }:
 
 stdenv.mkDerivation rec {
   name = "dapp-${version}";
@@ -16,7 +17,7 @@ stdenv.mkDerivation rec {
   postInstall =
     let
       path = lib.makeBinPath [
-        coreutils git gnused gnumake hevm jshon jq nix nodejs perl seth solc tre python3
+        coreutils findutils git gnused gnumake hevm jshon jq nix nodejs perl seth solc tre python3 ripgrep
       ];
     in
       ''

src/dapp/libexec/dapp/dapp-remappings

@@ -25,10 +25,20 @@ function buildDependencyTree(prefix) {
 
 // walk tree and build remappings
 function buildRemappings(pkg) {
-  const remappings = pkg.deps.map(dep => {
-    return `${pkg.path}/:${dep.name}/=${dep.path}/`
-  })
-  return pkg.deps.map(buildRemappings).concat(remappings).flat()
+  const paths = mapHashes(pkg)
+
+  let implicits = []
+  if (process.env.DAPP_ALLOW_IMPLICIT_IMPORTS == "yes") {
+    const directs = pkg.deps.map(p => p.name)
+    // get the transitive deps with exactly one version that are not direct deps
+    const uniques = Object.entries(pkg.deps.reduce(buildVersionMap, {}))
+                          .filter(([name, vs]) => vs.size == 1 && !directs.includes(name))
+    // build remappings that allow importing these deps from `pkg`
+    implicits = uniques.map(([name, v]) => `${pkg.path}/:${name}/=${paths[([...v][0])]}/`)
+  }
+
+  const remappings = pkg.deps.map(dep => `${pkg.path}/:${dep.name}/=${dep.path}/`)
+  return pkg.deps.map(buildRemappings).concat(remappings).concat(implicits).flat()
 }
 
 // walk tree and rewrite paths so that all packages with the same hash have the same path
@@ -47,6 +57,21 @@ function mapHashes(pkg) {
   return pkg.deps.reduce(go, { [pkg.hash]: pkg.path })
 }
 
+// folds over a dependency tree with map as the accumlator and builds a mapping
+// from package name to a set of discovered package verions
+function buildVersionMap(map, pkg) {
+  const update = (map, dep) => {
+    map[dep.name] == undefined
+      ? map[dep.name] = new Set([dep.hash])
+      : map[dep.name].add(dep.hash)
+    return map
+  }
+
+  return pkg.deps.reduce((versions, dep) => {
+    return update(versions, dep)
+  }, update(map, pkg))
+}
+
 // strip the leading `.` or `./` from a path
 function normalize(path) {
   return path.replace(/^\.\//, "").replace(/^\//, "")
@@ -56,9 +81,9 @@ function normalize(path) {
 // availalbe (because it's faster), or falls back to a sha256sum of the directory contents if needed
 function hash(dir) {
   if (ls(dir).includes(".git")) {
-    return run("git", ["-C", dir, "rev-parse", "HEAD"])
+    return run("git", ["-C", dir, "rev-parse", "HEAD"]).trim()
   } else {
-    return run("bash", ["-c", `rg --files ${dir} | sort | xargs sha256sum | sha256sum`])
+    return run("bash", ["-c", `rg --files ${dir} | sort | xargs sha256sum | sha256sum | cut -d' ' -f1`]).trim()
   }
 }