5 files changed, 52 insertions, 15 deletions
diff --git a/lib/std/compress.zig b/lib/std/compress.zig
index 200489c18a..7cc4a80d33 100644
--- a/lib/std/compress.zig
+++ b/lib/std/compress.zig
@@ -10,10 +10,7 @@ pub const lzma2 = @import("compress/lzma2.zig");
 pub const xz = @import("compress/xz.zig");
 pub const zstd = @import("compress/zstandard.zig");
 
-pub fn HashedReader(
-    comptime ReaderType: anytype,
-    comptime HasherType: anytype,
-) type {
+pub fn HashedReader(ReaderType: type, HasherType: type) type {
     return struct {
         child_reader: ReaderType,
         hasher: HasherType,
@@ -40,10 +37,7 @@ pub fn hashedReader(
     return .{ .child_reader = reader, .hasher = hasher };
 }
 
-pub fn HashedWriter(
-    comptime WriterType: anytype,
-    comptime HasherType: anytype,
-) type {
+pub fn HashedWriter(WriterType: type, HasherType: type) type {
     return struct {
         child_writer: WriterType,
         hasher: HasherType,
diff --git a/lib/std/crypto/phc_encoding.zig b/lib/std/crypto/phc_encoding.zig
index ee814861b3..507a02b983 100644
--- a/lib/std/crypto/phc_encoding.zig
+++ b/lib/std/crypto/phc_encoding.zig
@@ -75,6 +75,10 @@ pub fn BinValue(comptime max_len: usize) type {
 ///
 /// Other fields will also be deserialized from the function parameters section.
 pub fn deserialize(comptime HashResult: type, str: []const u8) Error!HashResult {
+    if (@hasField(HashResult, version_param_name)) {
+        @compileError("Field name '" ++ version_param_name ++ "'' is reserved for the algorithm version");
+    }
+
     var out = mem.zeroes(HashResult);
     var it = mem.splitScalar(u8, str, fields_delimiter_scalar);
     var set_fields: usize = 0;
@@ -198,6 +202,11 @@ pub fn calcSize(params: anytype) usize {
 
 fn serializeTo(params: anytype, out: anytype) !void {
     const HashResult = @TypeOf(params);
+
+    if (@hasField(HashResult, version_param_name)) {
+        @compileError("Field name '" ++ version_param_name ++ "'' is reserved for the algorithm version");
+    }
+
     try out.writeAll(fields_delimiter);
     try out.writeAll(params.alg_id);
 
diff --git a/lib/std/io/tty.zig b/lib/std/io/tty.zig
index 013057649e..c220e87880 100644
--- a/lib/std/io/tty.zig
+++ b/lib/std/io/tty.zig
@@ -12,9 +12,9 @@ const native_os = builtin.os.tag;
 pub fn detectConfig(file: File) Config {
     const force_color: ?bool = if (builtin.os.tag == .wasi)
         null // wasi does not support environment variables
-    else if (process.hasEnvVarConstant("NO_COLOR"))
+    else if (process.hasNonEmptyEnvVarConstant("NO_COLOR"))
         false
-    else if (process.hasEnvVarConstant("CLICOLOR_FORCE"))
+    else if (process.hasNonEmptyEnvVarConstant("CLICOLOR_FORCE"))
         true
     else
         null;
diff --git a/lib/std/process.zig b/lib/std/process.zig
index 34072a4d31..bc798e68e0 100644
--- a/lib/std/process.zig
+++ b/lib/std/process.zig
@@ -431,6 +431,20 @@ pub fn hasEnvVarConstant(comptime key: []const u8) bool {
     }
 }
 
+/// On Windows, `key` must be valid UTF-8.
+pub fn hasNonEmptyEnvVarConstant(comptime key: []const u8) bool {
+    if (native_os == .windows) {
+        const key_w = comptime unicode.utf8ToUtf16LeStringLiteral(key);
+        const value = getenvW(key_w) orelse return false;
+        return value.len != 0;
+    } else if (native_os == .wasi and !builtin.link_libc) {
+        @compileError("hasNonEmptyEnvVarConstant is not supported for WASI without libc");
+    } else {
+        const value = posix.getenv(key) orelse return false;
+        return value.len != 0;
+    }
+}
+
 pub const ParseEnvVarIntError = std.fmt.ParseIntError || error{EnvironmentVariableNotFound};
 
 /// Parses an environment variable as an integer.
@@ -477,6 +491,27 @@ pub fn hasEnvVar(allocator: Allocator, key: []const u8) HasEnvVarError!bool {
     }
 }
 
+/// On Windows, if `key` is not valid [WTF-8](https://simonsapin.github.io/wtf-8/),
+/// then `error.InvalidWtf8` is returned.
+pub fn hasNonEmptyEnvVar(allocator: Allocator, key: []const u8) HasEnvVarError!bool {
+    if (native_os == .windows) {
+        var stack_alloc = std.heap.stackFallback(256 * @sizeOf(u16), allocator);
+        const stack_allocator = stack_alloc.get();
+        const key_w = try unicode.wtf8ToWtf16LeAllocZ(stack_allocator, key);
+        defer stack_allocator.free(key_w);
+        const value = getenvW(key_w) orelse return false;
+        return value.len != 0;
+    } else if (native_os == .wasi and !builtin.link_libc) {
+        var envmap = getEnvMap(allocator) catch return error.OutOfMemory;
+        defer envmap.deinit();
+        const value = envmap.getPtr(key) orelse return false;
+        return value.len != 0;
+    } else {
+        const value = posix.getenv(key) orelse return false;
+        return value.len != 0;
+    }
+}
+
 /// Windows-only. Get an environment variable with a null-terminated, WTF-16 encoded name.
 ///
 /// This function performs a Unicode-aware case-insensitive lookup using RtlEqualUnicodeString.
diff --git a/lib/std/zig.zig b/lib/std/zig.zig
index d2521be1ba..46d164dade 100644
--- a/lib/std/zig.zig
+++ b/lib/std/zig.zig
@@ -697,6 +697,10 @@ pub const EnvVar = enum {
     XDG_CACHE_HOME,
     HOME,
 
+    pub fn isSet(comptime ev: EnvVar) bool {
+        return std.process.hasNonEmptyEnvVarConstant(@tagName(ev));
+    }
+
     pub fn get(ev: EnvVar, arena: std.mem.Allocator) !?[]u8 {
         if (std.process.getEnvVarOwned(arena, @tagName(ev))) |value| {
             return value;
@@ -709,11 +713,6 @@ pub const EnvVar = enum {
     pub fn getPosix(comptime ev: EnvVar) ?[:0]const u8 {
         return std.posix.getenvZ(@tagName(ev));
     }
-
-    pub fn isSet(ev: EnvVar, arena: std.mem.Allocator) !bool {
-        const value = try ev.get(arena) orelse return false;
-        return value.len != 0;
-    }
 };
 
 pub const SimpleComptimeReason = enum(u32) {