Add Go highlighting

assets/highlighting-tests/go.go

@@ -0,0 +1,130 @@
+// Line comment
+/*
+ * Multi-line
+ * comment
+ */
+
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+// Numbers
+const (
+	Dec  = 42
+	Neg  = -7
+	Hex  = 0xCAFE_BABE
+	Oct  = 0o755
+	Old  = 0755
+	Bin  = 0b1010
+	Sep  = 1_000_000
+	Flt  = 3.14
+	Half = .5
+	Exp  = 1e10
+	Sci  = 1.5e-3
+	Imag = 2.5i
+)
+
+// Constants and iota
+const (
+	A = iota
+	B
+)
+
+var (
+	yes  = true
+	no   = false
+	none = nil
+)
+
+// Predeclared types
+var (
+	b    bool
+	by   byte
+	r    rune
+	s    string
+	i    int
+	i8   int8
+	i64  int64
+	u    uint
+	u32  uint32
+	up   uintptr
+	f64  float64
+	c128 complex128
+	e    error
+	a    any
+)
+
+// Strings and runes
+var (
+	char    = 'a'
+	escaped = '\n'
+	quote   = '\''
+	str     = "double quotes with escapes: \" \n \t \\"
+	raw     = `raw string
+spans lines and may contain "quotes"`
+)
+
+type Speaker interface {
+	Speak() string
+}
+
+type Animal struct {
+	Name string `json:"name"`
+}
+
+func (a Animal) Speak() string {
+	return fmt.Sprintf("%s speaks", a.Name)
+}
+
+func compare[T comparable](a, b T) bool {
+	return a == b
+}
+
+func main() {
+	if yes {
+		fmt.Println("enabled")
+	} else {
+		fmt.Println("disabled")
+	}
+
+	for i := 0; i < 10; i++ {
+		switch {
+		case i == 5:
+			continue
+		case i == 8:
+			goto done
+		default:
+			fallthrough
+		}
+	}
+
+	switch now := time.Now().Weekday(); now {
+	case time.Saturday, time.Sunday:
+		fmt.Println("weekend")
+	}
+
+	values := []int{1, 2, 3}
+	m := map[string]int{"one": 1}
+	for _, value := range values {
+		fmt.Println(value, m)
+	}
+
+	ch := make(chan int, 1)
+	go func() {
+		defer close(ch)
+		ch <- 42
+	}()
+
+	select {
+	case msg := <-ch:
+		fmt.Println(msg)
+	default:
+		fmt.Println("no message")
+	}
+
+done:
+	var _ Speaker = Animal{Name: "dog"}
+}

assets/highlighting-tests/markdown.md

@@ -80,16 +80,6 @@ export function greet(name) {
 }
 ```
 
-```lua
-local function greet(name)
-    return "hello " .. name
-end
-```
-
-```luau
-export type Greeting = (name: string) -> string
-```
-
 ```python
 def greet(name: str) -> str:
     return f"hello {name}"

crates/lsh/definitions/go.lsh

@@ -0,0 +1,53 @@
+#[display_name = "Go"]
+#[path = "**/*.go"]
+pub fn go() {
+    until /$/ {
+        yield other;
+
+        if /\/\/.*/ {
+            yield comment;
+        } else if /\/\*/ {
+            loop {
+                yield comment;
+                await input;
+                if /\*\// {
+                    yield comment;
+                    break;
+                }
+            }
+        } else if /`/ {
+            loop {
+                yield string;
+                if /`/ {
+                    yield string;
+                    break;
+                }
+                await input;
+            }
+        } else if /'/ {
+            single_quote_string();
+        } else if /"/ {
+            double_quote_string();
+        } else if /(?:break|case|continue|default|defer|else|fallthrough|for|goto|go|if|range|return|select|switch)\>/ {
+            yield keyword.control;
+        } else if /(?:chan|const|func|import|interface|map|package|struct|type|var)\>/ {
+            yield keyword.other;
+        } else if /(?:true|false|iota|nil)\>/ {
+            yield constant.language;
+        } else if /(?:any|bool|byte|comparable|complex128|complex64|error|float32|float64|int8|int16|int32|int64|int|rune|string|uint8|uint16|uint32|uint64|uintptr|uint)\>/ {
+            yield storage.type;
+        } else if /(?i:-?(?:0x[\da-f_]+|0b[01_]+|0o[0-7_]+|\d[\d_]*\.?[\d_]*|\.[\d_]+)(?:[ep][+-]?[\d_]+)?i?)/ {
+            if /\w+/ {
+                // Invalid numeric literal
+            } else {
+                yield constant.numeric;
+            }
+        } else if /(\w+)\s*\(/ {
+            yield $1 as method;
+        } else if /\w+/ {
+            // Gobble word chars to align the next iteration on a word boundary.
+        }
+
+        yield other;
+    }
+}

crates/lsh/definitions/markdown.lsh

@@ -60,17 +60,7 @@ pub fn markdown() {
                     if /.*/ {}
                 }
             }
-        } else if /(?i:lua|luau)/ {
-            loop {
-                await input;
-                if /\s*```/ {
-                    return;
-                } else {
-                    lua();
-                    if /.*/ {}
-                }
-            }
-        } else if /(?i:py)/ {
+        } else if /(?i:py|python)/ {
             loop {
                 await input;
                 if /\s*```/ {