Detect when symlink not enabled

Author: dtolnay

gen/build/build.rs

@@ -0,0 +1,29 @@
+use std::io::{self, Write};
+use std::path::Path;
+use std::process;
+
+const NOSYMLINK: &str = "
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When building `cxx` from a git clone, git's symlink support needs
+to be enabled on platforms that have it off by default (Windows).
+Either use:
+
+   $ git config --global core.symlinks true
+
+prior to cloning, or else use:
+
+   $ git clone -c core.symlinks=true ...
+
+for the clone.
+
+Symlinks are only required for local development, not for building
+`cxx` as a (possibly transitive) dependency from crates.io.
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+";
+
+fn main() {
+    if !Path::new("src/syntax/mod.rs").exists() {
+        let _ = io::stderr().lock().write_all(NOSYMLINK.as_bytes());
+        process::exit(1);
+    }
+}

gen/cmd/build.rs

@@ -0,0 +1,29 @@
+use std::io::{self, Write};
+use std::path::Path;
+use std::process;
+
+const NOSYMLINK: &str = "
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When building `cxx` from a git clone, git's symlink support needs
+to be enabled on platforms that have it off by default (Windows).
+Either use:
+
+   $ git config --global core.symlinks true
+
+prior to cloning, or else use:
+
+   $ git clone -c core.symlinks=true ...
+
+for the clone.
+
+Symlinks are only required for local development, not for building
+`cxx` as a (possibly transitive) dependency from crates.io.
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+";
+
+fn main() {
+    if !Path::new("src/syntax/mod.rs").exists() {
+        let _ = io::stderr().lock().write_all(NOSYMLINK.as_bytes());
+        process::exit(1);
+    }
+}

gen/lib/build.rs

@@ -0,0 +1,29 @@
+use std::io::{self, Write};
+use std::path::Path;
+use std::process;
+
+const NOSYMLINK: &str = "
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When building `cxx` from a git clone, git's symlink support needs
+to be enabled on platforms that have it off by default (Windows).
+Either use:
+
+   $ git config --global core.symlinks true
+
+prior to cloning, or else use:
+
+   $ git clone -c core.symlinks=true ...
+
+for the clone.
+
+Symlinks are only required for local development, not for building
+`cxx` as a (possibly transitive) dependency from crates.io.
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+";
+
+fn main() {
+    if !Path::new("src/syntax/mod.rs").exists() {
+        let _ = io::stderr().lock().write_all(NOSYMLINK.as_bytes());
+        process::exit(1);
+    }
+}

macro/build.rs

@@ -0,0 +1,29 @@
+use std::io::{self, Write};
+use std::path::Path;
+use std::process;
+
+const NOSYMLINK: &str = "
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When building `cxx` from a git clone, git's symlink support needs
+to be enabled on platforms that have it off by default (Windows).
+Either use:
+
+   $ git config --global core.symlinks true
+
+prior to cloning, or else use:
+
+   $ git clone -c core.symlinks=true ...
+
+for the clone.
+
+Symlinks are only required for local development, not for building
+`cxx` as a (possibly transitive) dependency from crates.io.
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+";
+
+fn main() {
+    if !Path::new("src/syntax/mod.rs").exists() {
+        let _ = io::stderr().lock().write_all(NOSYMLINK.as_bytes());
+        process::exit(1);
+    }
+}