3 files changed, 25 insertions, 152 deletions
diff --git a/Cargo.lock b/Cargo.lock
index 05d340e5f..4ef0134d7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -353,11 +353,6 @@ dependencies = [
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 [[package]]
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-[[package]]
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@@ -407,15 +402,6 @@ version = "0.3.5"
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 [[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
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@@ -558,11 +544,6 @@ dependencies = [
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@@ -587,21 +568,6 @@ dependencies = [
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@@ -1009,11 +975,6 @@ dependencies = [
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@@ -1368,7 +1329,6 @@ dependencies = [
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-[[package]]
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@@ -1870,36 +1822,6 @@ dependencies = [
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 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
diff --git a/crates/ra_tools/Cargo.toml b/crates/ra_tools/Cargo.toml
index a40a452aa..4c9aa1cc3 100644
--- a/crates/ra_tools/Cargo.toml
+++ b/crates/ra_tools/Cargo.toml
@@ -6,7 +6,6 @@ authors = ["rust-analyzer developers"]
 publish = false
 [dependencies]
-teraron = "0.1.0"
 walkdir = "2.1.3"
 itertools = "0.8.0"
 clap = "2.32.0"
diff --git a/crates/ra_tools/src/lib.rs b/crates/ra_tools/src/lib.rs
index de8c472d1..c02dee953 100644
--- a/crates/ra_tools/src/lib.rs
+++ b/crates/ra_tools/src/lib.rs
@@ -11,8 +11,6 @@ use std::{
 use itertools::Itertools;
-pub use teraron::{Mode, Overwrite, Verify};
 pub use self::codegen::generate;
 pub type Result<T> = std::result::Result<T, Box<dyn Error>>;
@@ -26,6 +24,13 @@ pub const SYNTAX_KINDS: &str = "crates/ra_parser/src/syntax_kind/generated.rs.te
 pub const AST: &str = "crates/ra_syntax/src/ast/generated.rs";
 const TOOLCHAIN: &str = "stable";
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub enum Mode {
+    Overwrite,
+    Verify,
+}
+pub use Mode::*;
 #[derive(Debug)]
 pub struct Test {
    pub name: String,
@@ -222,7 +227,7 @@ pub fn gen_tests(mode: Mode) -> Result<()> {
                    tests_dir.join(file_name)
                }
            };
-            teraron::update(&path, &test.text, mode)?;
+            update(&path, &test.text, mode)?;
        }
        Ok(())
    }
@@ -306,3 +311,20 @@ fn existing_tests(dir: &Path, ok: bool) -> Result<HashMap<String, (PathBuf, Test
    }
    Ok(res)
 }
+/// A helper to update file on disk if it has changed.
+/// With verify = false,
+pub fn update(path: &Path, contents: &str, mode: Mode) -> Result<()> {
+    match fs::read_to_string(path) {
+        Ok(ref old_contents) if old_contents == contents => {
+            return Ok(());
+        }
+        _ => (),
+    }
+    if mode == Verify {
+        Err(format!("`{}` is not up-to-date", path.display()))?;
+    }
+    eprintln!("updating {}", path.display());
+    fs::write(path, contents)?;
+    Ok(())
+}