fix: Reduce deps for users

Markdown parsers and more are foited onto clients because of Skeptic.
This is inspired by the conversation at budziq/rust-skeptic#60 regarding
a "skeptic-lite" using rustdoc.

Cargo.toml

@@ -10,8 +10,6 @@ categories = ["template-engine"]
 keywords = ["liquid", "template", "templating", "language", "html"]
 license = "MIT"
 
-build = "build.rs"
-
 [badges]
 travis-ci = { repository = "cobalt-org/liquid-rust" }
 appveyor  = { repository = "cobalt-org/liquid-rust" }
@@ -46,10 +44,8 @@ serde_yaml = { version = "0.7", optional = true }
 serde_json = { version = "1.0", optional = true }
 
 [build-dependencies]
-skeptic = "0.13.2"
 serde = { version = "1.0", features = ["derive"] }
 
 [dev-dependencies]
 difference = "2.0"
-skeptic = "0.13.2"
 serde_yaml = "0.7"

README.md

@@ -13,13 +13,17 @@ To include liquid in your project add the following to your Cargo.toml:
 liquid = "0.14"
 ```
 
-Now you can use the crate in your code
+Now you can use the crate in your code:
+
 ```rust
 extern crate liquid;
 ```
 
 Example:
+
 ```rust
+extern crate liquid;
+
 let template = liquid::ParserBuilder::with_liquid()
     .build()
     .parse("Liquid! {{num | minus: 2}}").unwrap();
@@ -73,14 +77,3 @@ See
 [comment_block.rs](https://github.com/cobalt-org/liquid-rust/blob/master/src/tags/comment_block.rs)
 for what a block implementation looks like.  You can then register it by
 calling `liquid::ParserBuilder::block`.
-
-----------
-
-<!---
-
-Skeptic template:
-```rust,skeptic-template
-extern crate skeptic; extern crate liquid; fn main() {{ {} }}
-```
-
--->

tests/skeptic.rs

@@ -1 +1,39 @@
-include!(concat!(env!("OUT_DIR"), "/skeptic-tests.rs"));
+use std::env;
+use std::env::consts::EXE_EXTENSION;
+use std::path::Path;
+use std::process::Command;
+
+#[test]
+fn readme_test() {
+    let rustdoc = Path::new("rustdoc").with_extension(EXE_EXTENSION);
+    let readme = Path::new(file!())
+        .parent()
+        .unwrap()
+        .parent()
+        .unwrap()
+        .join("README.md");
+    let exe = env::current_exe().unwrap();
+    let depdir = exe.parent().unwrap();
+    let outdir = depdir.parent().unwrap();
+    let extern_arg = format!(
+        "read_process_memory={}",
+        outdir.join("libread_process_memory.rlib").to_string_lossy()
+    );
+    let mut cmd = Command::new(rustdoc);
+    cmd.args(&["--verbose", "--test", "-L"])
+        .arg(&outdir)
+        .arg("-L")
+        .arg(&depdir)
+        .arg("--extern")
+        .arg(&extern_arg)
+        .arg(&readme);
+    println!("Running `{:?}`", cmd);
+    let result = cmd.spawn()
+        .expect("Failed to spawn process")
+        .wait()
+        .expect("Failed to run process");
+    assert!(
+        result.success(),
+        "Failed to run rustdoc tests on README.md!"
+    );
+}