More relative path fixes

src/generate.ts

@@ -45,14 +45,16 @@ export default async (
     return;
   }
 
-  // Sanity checks.
-  const yarnPathAbs = configuration.get(`yarnPath`);
+  // Determine relative paths for Nix path literals.
   const nixExprPath = configuration.get(`nixExprPath`);
-  let yarnPath: PortablePath;
+
+  const yarnPathAbs = configuration.get(`yarnPath`);
+  let yarnPathExpr: string;
   if (yarnPathAbs.startsWith(cwd)) {
-    yarnPath = ppath.relative(ppath.dirname(nixExprPath), yarnPathAbs);
+    yarnPathExpr =
+      "./" + ppath.relative(ppath.dirname(nixExprPath), yarnPathAbs);
   } else {
-    yarnPath = yarnPathAbs;
+    yarnPathExpr = json(yarnPathAbs);
     report.reportWarning(
       0,
       `The Yarn path ${yarnPathAbs} is outside the project - it may not be reachable by the Nix build`
@@ -60,29 +62,42 @@ export default async (
   }
 
   const cacheFolderAbs = configuration.get(`cacheFolder`);
-  let cacheFolder = ppath.relative(cwd, cacheFolderAbs);
-  if (cacheFolder.startsWith(`../`)) {
-    cacheFolder = cacheFolderAbs;
+  let cacheFolderExpr: string;
+  if (cacheFolderAbs.startsWith(cwd)) {
+    cacheFolderExpr =
+      "./" + ppath.relative(ppath.dirname(nixExprPath), cacheFolderAbs);
+  } else {
+    cacheFolderExpr = json(cacheFolderAbs);
     report.reportWarning(
       0,
       `The cache folder ${cacheFolderAbs} is outside the project - it may not be reachable by the Nix build`
     );
   }
 
-  for (const source of configuration.sources.values()) {
+  const configSources = new Set();
+  for (const sourceList of configuration.sources.values()) {
+    for (const source of sourceList.split(", ")) {
       if (!source.startsWith(`<`)) {
-      const relativeSource = ppath.relative(cwd, source as PortablePath);
-      if (relativeSource.startsWith(`../`)) {
+        configSources.add(source);
+      }
+    }
+  }
+  for (const source of configSources) {
+    const relativeSource = ppath.resolve(cwd, source as PortablePath);
+    if (!relativeSource.startsWith(cwd)) {
       report.reportWarning(
         0,
         `The config file ${source} is outside the project - it may not be reachable by the Nix build`
       );
     }
   }
-  }
 
-  // Determine relative paths for Nix path literals.
-  const lockfileFilename = configuration.get(`lockfileFilename`);
+  const lockfileExpr =
+    "./" +
+    ppath.relative(
+      ppath.dirname(nixExprPath),
+      ppath.resolve(cwd, configuration.get(`lockfileFilename`))
+    );
 
   // Build a list of cache entries so Nix can fetch them.
   // TODO: See if we can use Nix fetchurl for npm: dependencies.
@@ -278,9 +293,9 @@ export default async (
     const projectName = ident ? structUtils.stringifyIdent(ident) : `workspace`;
     const projectExpr = renderTmpl(projectExprTmpl, {
       PROJECT_NAME: json(projectName),
-      YARN_PATH: yarnPath,
-      LOCKFILE: lockfileFilename,
-      CACHE_FOLDER: json(cacheFolder),
+      YARN_PATH: yarnPathExpr,
+      LOCKFILE: lockfileExpr,
+      CACHE_FOLDER: cacheFolderExpr,
       CACHE_ENTRIES: cacheEntriesCode,
       ISOLATED: isolatedCode.join("\n"),
       ISOLATED_INTEGRATION: indent("      ", isolatedIntegration.join("\n")),

src/tmpl/yarn-project.nix.in

@@ -7,9 +7,7 @@
 let
 
   cacheFolder = @@CACHE_FOLDER@@;
-#@@ IF NEED_ISOLATED_BUILD_SUPPRORT
-  lockfile = ./@@LOCKFILE@@;
-#@@ ENDIF NEED_ISOLATED_BUILD_SUPPRORT
+  lockfile = @@LOCKFILE@@;
 
   # Call overrideAttrs on a derivation if a function is provided.
   optionalOverride = fn: drv:
@@ -17,7 +15,7 @@ let
 
   # Simple stub that provides the global yarn command.
   yarn = writeShellScriptBin "yarn" ''
-    exec '${nodejs}/bin/node' '${./@@YARN_PATH@@}' "$@"
+    exec '${nodejs}/bin/node' '${@@YARN_PATH@@}' "$@"
   '';
 
   # Common attributes between Yarn derivations.
@@ -164,7 +162,7 @@ let
         mkdir -p "$out/libexec/$name"
         tar xzvf package.tgz --directory "$out/libexec/$name" --strip-components=1
 
-        cp .yarnrc* '@@LOCKFILE@@' "$out/libexec/$name"
+        cp .yarnrc* ${lockfile} "$out/libexec/$name"
         cp --recursive .yarn "$out/libexec/$name"
 
         # If the project uses the node-modules linker, then