Merge pull request #6818 from ZZBaron/nix/devshell-support

Fix Nix Package Detection in nix-shell Environment

Author: waruqi

xmake/modules/package/manager/nix/find_package.lua

@@ -24,13 +24,113 @@ import("lib.detect.find_tool")
 import("private.core.base.is_cross")
 import("package.manager.pkgconfig.find_package", {alias = "find_package_from_pkgconfig"})
 
+-- check if we're in a nix-shell environment
+function _in_nix_shell()
+    local in_nix_shell = os.getenv("IN_NIX_SHELL")
+    return in_nix_shell == "pure" or in_nix_shell == "impure"
+end
+
+-- extract store paths from nix environment variables with better filtering
+function _extract_nix_store_paths(env_var_name, env_var_value)
+    local paths = {}
+    local seen = {}
+    
+    if env_var_value == "" then
+        return paths
+    end
+    
+    -- Handle different environment variable formats
+    local separators = {
+        PATH = ":",
+        PKG_CONFIG_PATH = ":",
+        LIBRARY_PATH = ":",
+        LD_LIBRARY_PATH = ":",
+        C_INCLUDE_PATH = ":",
+        CPLUS_INCLUDE_PATH = ":",
+        NIX_LDFLAGS = "%s",  -- space separated, may contain -L flags
+        NIX_CFLAGS_COMPILE = "%s"  -- space separated, may contain -I flags
+    }
+    
+    local separator = separators[env_var_name] or ":"
+    local pattern = separator == ":" and "[^:]+" or "[^%s]+"
+    
+    for item in env_var_value:gmatch(pattern) do
+        local clean_item = item
+        
+        -- Remove flag prefixes for compiler/linker flags
+        if env_var_name == "NIX_LDFLAGS" then
+            clean_item = item:gsub("^%-L", "")
+        elseif env_var_name == "NIX_CFLAGS_COMPILE" then
+            clean_item = item:gsub("^%-[iI]system%s*", ""):gsub("^%-I", "")
+        end
+        
+        if clean_item:startswith("/nix/store/") then
+            local store_path = clean_item:match("(/nix/store/[^/]+)")
+            if store_path and not seen[store_path] then
+                seen[store_path] = true
+                table.insert(paths, store_path)
+            end
+        end
+    end
+    
+    return paths
+end
+
+-- get current shell buildInputs from environment with improved detection
+function _get_shell_build_inputs()
+    local all_paths = {}
+    local seen = {}
+    
+    if not _in_nix_shell() then
+        return all_paths
+    end
+    
+    -- Environment variables to check for nix store paths
+    local env_vars = {
+        "PATH",
+        "PKG_CONFIG_PATH", 
+        "LIBRARY_PATH",
+        "LD_LIBRARY_PATH",
+        "C_INCLUDE_PATH",
+        "CPLUS_INCLUDE_PATH",
+        "NIX_LDFLAGS",
+        "NIX_CFLAGS_COMPILE"
+    }
+    
+    for _, env_var in ipairs(env_vars) do
+        local env_value = os.getenv(env_var) or ""
+        local paths = _extract_nix_store_paths(env_var, env_value)
+        
+        for _, path in ipairs(paths) do
+            if not seen[path] then
+                seen[path] = true
+                table.insert(all_paths, path)
+            end
+        end
+    end
+    
+    return all_paths
+end
+
 -- get all nix store paths currently available in environment
 function _get_available_nix_paths()
     local paths = {}
     local seen = {}
 
-    -- Get paths from environment PATH
+    -- First, get paths from current shell if we're in nix-shell
+    if _in_nix_shell() then
+        local shell_paths = _get_shell_build_inputs()
+        for _, path in ipairs(shell_paths) do
+            if not seen[path] then
+                seen[path] = true
+                table.insert(paths, path)
+            end
+        end
+    end
+    
+    -- Get paths from environment PATH (additional check)
     local env_path = os.getenv("PATH") or ""
+    
     for dir in env_path:gmatch("[^:]+") do
         if dir:startswith("/nix/store/") then
             local store_path = dir:match("(/nix/store/[^/]+)")
@@ -46,11 +146,12 @@ function _get_available_nix_paths()
         os.getenv("NIX_PROFILES") or "",
         (os.getenv("HOME") or "") .. "/.nix-profile",
         "/nix/var/nix/profiles/default",
-        "/run/current-system/sw" -- NixOS system packages
+        "/run/current-system/sw" -- NixOS
     }
 
     for _, location in ipairs(env_locations) do
         if location ~= "" and os.isdir(location) then
+            
             -- Check if it's a symlink to store path
             local target = try {function()
                 return os.iorunv("readlink", {"-f", location}):trim()
@@ -81,16 +182,64 @@ function _get_available_nix_paths()
             end
         end
     end
-    
+
     return paths
 end
 
--- find package in a specific nix store path
+-- check if a store path actually contains the requested package
+function _validate_package_in_store_path(store_path, name)
+    
+    -- Check if the store path name contains the package name
+    local store_name = path.basename(store_path):lower()
+    local search_name = name:lower()
+    
+    -- Look for exact match, or package name in the store path
+    local name_match = store_name:find(search_name, 1, true) or 
+                      store_name:find((search_name:gsub("%-", "%%-"))) -- handle hyphens
+    
+    if name_match then
+        return true
+    end
+    
+    -- Check for libraries with the package name
+    local libdir = path.join(store_path, "lib")
+    if os.isdir(libdir) then
+        local libfiles = os.files(path.join(libdir, "lib" .. name .. ".*"))
+        if #libfiles > 0 then
+            return true
+        end
+    end
+    
+    -- Check for pkg-config files
+    local pkgconfigdirs = {
+        path.join(store_path, "lib", "pkgconfig"),
+        path.join(store_path, "share", "pkgconfig")
+    }
+    
+    for _, pcdir in ipairs(pkgconfigdirs) do
+        if os.isdir(pcdir) then
+            local pcfiles = os.files(path.join(pcdir, name .. ".pc"))
+            if #pcfiles > 0 then
+                return true
+            end
+        end
+    end
+
+    return false
+end
+
+-- find package in a specific nix store path with validation
 function _find_in_store_path(store_path, name)
+    
     if not os.isdir(store_path) then
         return nil
     end
 
+    -- First validate that this store path actually contains our package
+    if not _validate_package_in_store_path(store_path, name) then
+        return nil
+    end
+    
     local result = {}
 
     -- Find include directories
@@ -106,7 +255,7 @@ function _find_in_store_path(store_path, name)
         result.links = {}
         result.libfiles = {}
 
-        -- Scan for library files
+        -- Scan for library files related to our package
         local libfiles = os.files(path.join(libdir, "*.so*"), 
                                 path.join(libdir, "*.a"), 
                                 path.join(libdir, "*.dylib*"))
@@ -118,8 +267,10 @@ function _find_in_store_path(store_path, name)
                            filename:match("^lib(.+)%.dylib")
 
             if linkname then
-                table.insert(result.links, linkname)
-                table.insert(result.libfiles, libfile)
+                if linkname == name or linkname:find(name, 1, true) then
+                    table.insert(result.links, linkname)
+                    table.insert(result.libfiles, libfile)
+                end
 
                 if filename:endswith(".a") then
                     result.static = true
@@ -151,7 +302,7 @@ function _find_in_store_path(store_path, name)
     end
 
     -- Return result if we found anything useful
-    if result.includedirs or result.linkdirs then
+    if result.includedirs or (result.links and #result.links > 0) then
         return result
     end
 
@@ -208,9 +359,9 @@ function main(name, opt)
     -- Get all available Nix store paths
     local nix_paths = _get_available_nix_paths()
 
-    -- Search through available paths first (unless we're forced to build)
-    if #nix_paths > 0 and not force_nix then
-        for _, store_path in ipairs(nix_paths) do
+    -- Search through available paths first (prioritize shell environment)
+    if #nix_paths > 0 then
+        for i, store_path in ipairs(nix_paths) do
             local result = _find_in_store_path(store_path, actual_name)
             if result then
                 if opt.verbose or option.get("verbose") then
@@ -221,24 +372,26 @@ function main(name, opt)
         end
     end
 
-    -- If not found in available paths or forced to build, try building
-    local storepath = nil
-    
-    -- Try modern nix first
-    storepath = _try_modern_nix_build(actual_name)
-    
-    -- Fallback to legacy nix-build
-    if not storepath then
-        storepath = _try_legacy_nix_build(actual_name)
-    end
-    
-    if storepath and os.isdir(storepath) then
-        local result = _find_in_store_path(storepath, actual_name)
-        if result then
-            if opt.verbose or option.get("verbose") then
-                print("Built and found " .. actual_name .. " in: " .. storepath)
+    -- If not found in available paths and not in nix-shell, try building
+    if not _in_nix_shell() or force_nix then
+        local storepath = nil
+        
+        -- Try modern nix first
+        storepath = _try_modern_nix_build(actual_name)
+        
+        -- Fallback to legacy nix-build
+        if not storepath then
+            storepath = _try_legacy_nix_build(actual_name)
+        end
+        
+        if storepath and os.isdir(storepath) then
+            local result = _find_in_store_path(storepath, actual_name)
+            if result then
+                if opt.verbose or option.get("verbose") then
+                    print("Built and found " .. actual_name .. " in: " .. storepath)
+                end
+                return result
             end
-            return result
         end
     end