6 files changed, 76 insertions, 22 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 2e86b3fee..df79334c9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -884,9 +884,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.6"
+version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54a21852a652ad6f610c9510194f398ff6f8692e334fd1145fed931f7fbe44ea"
+checksum = "aa563d17ecb180e500da1cfd2b028310ac758de548efdd203e18f283af693f37"
 dependencies = [
  "proc-macro2",
 ]
diff --git a/crates/ra_ide/src/snapshots/highlight_strings.html b/crates/ra_ide/src/snapshots/highlight_strings.html
index e97192b61..6a5cf0e74 100644
--- a/crates/ra_ide/src/snapshots/highlight_strings.html
+++ b/crates/ra_ide/src/snapshots/highlight_strings.html
@@ -63,7 +63,7 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="macro">println!</span>(<span class="string_literal">"Hello </span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">^</span><span class="numeric_literal">5</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="string_literal">"x"</span>);
     <span class="macro">println!</span>(<span class="string_literal">"Hello </span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">&gt;</span><span class="numeric_literal">5</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="string_literal">"x"</span>);
     <span class="macro">println!</span>(<span class="string_literal">"Hello </span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">+</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="numeric_literal">5</span>);
-    <span class="macro">println!</span>(<span class="string_literal">"</span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">#</span><span class="variable">x</span><span class="string_literal">}!"</span>, <span class="numeric_literal">27</span>);
+    <span class="macro">println!</span>(<span class="string_literal">"</span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">#</span><span class="variable">x</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="numeric_literal">27</span>);
     <span class="macro">println!</span>(<span class="string_literal">"Hello </span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="numeric_literal">0</span><span class="numeric_literal">5</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="numeric_literal">5</span>);
     <span class="macro">println!</span>(<span class="string_literal">"Hello </span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="numeric_literal">0</span><span class="numeric_literal">5</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, -<span class="numeric_literal">5</span>);
     <span class="macro">println!</span>(<span class="string_literal">"</span><span class="format_specifier">{</span><span class="format_specifier">:</span><span class="format_specifier">#</span><span class="numeric_literal">0</span><span class="numeric_literal">10</span><span class="variable">x</span><span class="format_specifier">}</span><span class="string_literal">!"</span>, <span class="numeric_literal">27</span>);
diff --git a/crates/ra_syntax/src/ast/tokens.rs b/crates/ra_syntax/src/ast/tokens.rs
index 04b0a4480..56378385a 100644
--- a/crates/ra_syntax/src/ast/tokens.rs
+++ b/crates/ra_syntax/src/ast/tokens.rs
@@ -335,16 +335,26 @@ pub trait HasFormatSpecifier: AstToken {
                             }
                             c if c == '_' || c.is_alphabetic() => {
                                 read_identifier(&mut chars, &mut callback);
-                                if chars.peek().and_then(|next| next.1.as_ref().ok()).copied()
-                                    != Some('$')
-                                {
-                                    continue;
-                                }
-                                skip_char_and_emit(
-                                    &mut chars,
-                                    FormatSpecifier::DollarSign,
-                                    &mut callback,
-                                );
+                                // can be either width (indicated by dollar sign, or type in which case
+                                // the next sign has to be `}`)
+                                let next =
+                                    chars.peek().and_then(|next| next.1.as_ref().ok()).copied();
+                                match next {
+                                    Some('$') => skip_char_and_emit(
+                                        &mut chars,
+                                        FormatSpecifier::DollarSign,
+                                        &mut callback,
+                                    ),
+                                    Some('}') => {
+                                        skip_char_and_emit(
+                                            &mut chars,
+                                            FormatSpecifier::Close,
+                                            &mut callback,
+                                        );
+                                        continue;
+                                    }
+                                    _ => continue,
+                                };
                             }
                             _ => {}
                         }
@@ -416,12 +426,11 @@ pub trait HasFormatSpecifier: AstToken {
                         }
                     }
 
-                    let mut cloned = chars.clone().take(2);
-                    let first = cloned.next().and_then(|next| next.1.as_ref().ok()).copied();
-                    if first != Some('}') {
+                    if let Some((_, Ok('}'))) = chars.peek() {
+                        skip_char_and_emit(&mut chars, FormatSpecifier::Close, &mut callback);
+                    } else {
                         continue;
                     }
-                    skip_char_and_emit(&mut chars, FormatSpecifier::Close, &mut callback);
                 }
                 _ => {
                     while let Some((_, Ok(next_char))) = chars.peek() {
diff --git a/docs/dev/README.md b/docs/dev/README.md
index 194a40e15..903cb4055 100644
--- a/docs/dev/README.md
+++ b/docs/dev/README.md
@@ -184,6 +184,27 @@ use crate::{}
 use super::{} // but prefer `use crate::`
 ```
 
+## Import Style
+
+Items from `hir` and `ast` should be used qualified:
+
+```rust
+// Good
+use ra_syntax::ast;
+
+fn frobnicate(func: hir::Function, strukt: ast::StructDef) {}
+
+// Not as good
+use hir::Function;
+use ra_syntax::ast::StructDef;
+
+fn frobnicate(func: Function, strukt: StructDef) {}
+```
+
+Avoid local `use MyEnum::*` imports.
+
+Prefer `use crate::foo::bar` to `use super::bar`.
+
 ## Order of Items
 
 Optimize for the reader who sees the file for the first time, and wants to get the general idea about what's going on.
@@ -220,6 +241,33 @@ struct Foo {
 For `.md` and `.adoc` files, prefer a sentence-per-line format, don't wrap lines.
 If the line is too long, you want to split the sentence in two :-)
 
+# Architecture Invariants
+
+This section tries to document high-level design constraints, which are not
+always obvious from the low-level code.
+
+## Incomplete syntax trees
+
+Syntax trees are by design incomplete and do not enforce well-formedness.
+If ast method returns an `Option`, it *can* be `None` at runtime, even if this is forbidden by the grammar.
+
+## LSP indenpendence
+
+rust-analyzer is independent from LSP.
+It provides features for a hypothetical perfect Rust-specific IDE client.
+Internal representations are lowered to LSP in the `rust-analyzer` crate (the only crate which is allowed to use LSP types).
+
+## IDE/Compiler split
+
+There's a semi-hard split between "compiler" and "IDE", at the `ra_hir` crate.
+Compiler derives new facts about source code.
+It explicitly acknowledges that not all info is available (ie, you can't look at types during name resolution).
+
+IDE assumes that all information is available at all times.
+
+IDE should use only types from `ra_hir`, and should not depend on the underling compiler types.
+`ra_hir` is a facade.
+
 # Logging
 
 Logging is done by both rust-analyzer and VS Code, so it might be tricky to
diff --git a/editors/code/package.json b/editors/code/package.json
index b9c57db3b..859ab4477 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -487,10 +487,7 @@
                     "default": true
                 },
                 "rust-analyzer.linkedProjects": {
-                    "markdownDescription": [
-                        "Disable project auto-discovery in favor of explicitly specified set of projects.",
-                        "Elements must be paths pointing to Cargo.toml, rust-project.json, or JSON objects in rust-project.json format"
-                    ],
+                    "markdownDescription": "Disable project auto-discovery in favor of explicitly specified set of projects.  \nElements must be paths pointing to Cargo.toml, rust-project.json, or JSON objects in rust-project.json format",
                     "type": "array",
                     "items": {
                         "type": [
diff --git a/editors/code/src/run.ts b/editors/code/src/run.ts
index 5c790741f..bb060cfe1 100644
--- a/editors/code/src/run.ts
+++ b/editors/code/src/run.ts
@@ -110,7 +110,7 @@ export function createTask(runnable: ra.Runnable): vscode.Task {
     switch (runnable.kind) {
         case "cargo": command = toolchain.getPathForExecutable("cargo");
     }
-    const args = runnable.args.cargoArgs;
+    const args = [...runnable.args.cargoArgs]; // should be a copy!
     if (runnable.args.executableArgs.length > 0) {
         args.push('--', ...runnable.args.executableArgs);
     }