refactor(function-exists): drop checks for always-present capabilities

function_exists() returns false in PHP when a function is blocked by
disable_functions, when its extension is not compiled in, or when the
PHP version predates it. None of those apply to a native binary.

4 files changed, 19 insertions, 79 deletions

diff --git a/crates/shirabe/src/util/filesystem.rs b/crates/shirabe/src/util/filesystem.rs
index 41b81b7b..2395d1cd 100644
--- a/crates/shirabe/src/util/filesystem.rs
+++ b/crates/shirabe/src/util/filesystem.rs
@@ -6,11 +6,11 @@ use crate::util::Silencer;
 use shirabe_php_shim::{
     ErrorException, LogicException, PhpMixed, PregMatches, RuntimeException, array_pop, basename,
     chdir, clearstatcache, clearstatcache2, copy, dirname, explode, fclose, feof, file_exists,
-    file_get_contents, file_put_contents, fileatime, filemtime, filesize, fopen, fread,
-    function_exists, fwrite, implode, is_dir, is_file, is_link, is_readable, lstat, mkdir,
-    php_regex, preg_is_match, preg_match, preg_replace, preg_replace_callback, rename, rmdir,
-    rtrim, str_repeat, str_replace, strlen, strpos, strtoupper, strtr, substr, substr_count,
-    symlink, touch, unlink, usleep, var_export,
+    file_get_contents, file_put_contents, fileatime, filemtime, filesize, fopen, fread, fwrite,
+    implode, is_dir, is_file, is_link, is_readable, lstat, mkdir, php_regex, preg_is_match,
+    preg_match, preg_replace, preg_replace_callback, rename, rmdir, rtrim, str_repeat, str_replace,
+    strlen, strpos, strtoupper, strtr, substr, substr_count, symlink, touch, unlink, usleep,
+    var_export,
 };
 use shirabe_symfony_filesystem::exception::IOException;
 use shirabe_symfony_finder::Finder;
@@ -114,9 +114,6 @@ impl Filesystem {
     }
 
     /// Recursively remove a directory
-    ///
-    /// Uses the process component if proc_open is enabled on the PHP
-    /// installation.
     pub fn remove_directory(&mut self, directory: impl AsRef<Path>) -> anyhow::Result<bool> {
         // TODO(bytes):
         // This path is matched against a regex (remove_edge_cases) and passed to an
@@ -129,7 +126,7 @@ impl Filesystem {
                 directory.display()
             ))
         })?;
-        let edge_case_result = self.remove_edge_cases(directory, true)?;
+        let edge_case_result = self.remove_edge_cases(directory)?;
         if let Some(r) = edge_case_result {
             return Ok(r);
         }
@@ -167,13 +164,6 @@ impl Filesystem {
     }
 
     /// Recursively remove a directory asynchronously
-    ///
-    /// Uses the process component if proc_open is enabled on the PHP
-    /// installation.
-    ///
-    /// Takes the shared handle instead of `&mut self`: the Filesystem is borrowed only for the
-    /// synchronous head and tail, never across the subprocess await, so sibling futures can keep
-    /// using the same `Rc<RefCell<Filesystem>>` while the removal runs.
     pub async fn remove_directory_async_via(
         this: &std::rc::Rc<std::cell::RefCell<Filesystem>>,
         directory: &str,
@@ -189,7 +179,7 @@ impl Filesystem {
                 return Ok(result);
             }
 
-            let edge_case_result = fs.remove_edge_cases(directory, true)?;
+            let edge_case_result = fs.remove_edge_cases(directory)?;
             if let Some(r) = edge_case_result {
                 return Ok(r);
             }
@@ -225,11 +215,7 @@ impl Filesystem {
     }
 
     /// Returns null when no edge case was hit. Otherwise a bool whether removal was successful
-    fn remove_edge_cases(
-        &mut self,
-        directory: &str,
-        fallback_to_php: bool,
-    ) -> anyhow::Result<Option<bool>> {
+    fn remove_edge_cases(&mut self, directory: &str) -> anyhow::Result<Option<bool>> {
         if self.is_symlinked_directory(directory) {
             return Ok(Some(self.unlink_symlinked_directory(directory)?));
         }
@@ -251,10 +237,6 @@ impl Filesystem {
             .into());
         }
 
-        if !function_exists("proc_open") && fallback_to_php {
-            return Ok(Some(self.remove_directory_php(directory)?));
-        }
-
         Ok(None)
     }
 
@@ -264,7 +246,7 @@ impl Filesystem {
     /// before directories, creating a single non-recursive loop
     /// to delete files/directories in the correct order.
     pub fn remove_directory_php(&mut self, directory: &str) -> anyhow::Result<bool> {
-        let edge_case_result = self.remove_edge_cases(directory, false)?;
+        let edge_case_result = self.remove_edge_cases(directory)?;
         if let Some(r) = edge_case_result {
             return Ok(r);
         }
@@ -497,10 +479,6 @@ impl Filesystem {
             RuntimeException::new(format!("Path contains invalid UTF-8: {}", target.display()))
         })?;
 
-        if !function_exists("proc_open") {
-            return self.copy_then_remove(source, target);
-        }
-
         if Platform::is_windows() {
             // Try to copy & delete - this is a workaround for random "Access denied" errors.
             let mut output = String::new();
@@ -884,10 +862,6 @@ impl Filesystem {
 
     /// Creates a relative symlink from $link to $target
     pub fn relative_symlink(&self, target: &str, link: &str) -> bool {
-        if !function_exists("symlink") {
-            return false;
-        }
-
         let cwd = Platform::get_cwd(false).unwrap_or_default();
 
         let relative_path = self.find_shortest_path(link, target, false, false);
diff --git a/crates/shirabe/src/util/http_downloader.rs b/crates/shirabe/src/util/http_downloader.rs
index 36ccb712..8d34dcdf 100644
--- a/crates/shirabe/src/util/http_downloader.rs
+++ b/crates/shirabe/src/util/http_downloader.rs
@@ -19,8 +19,8 @@ use indexmap::IndexMap;
 use shirabe_php_shim::Catch as _;
 use shirabe_php_shim::{
     InvalidArgumentException, LogicException, PhpMixed, array_replace_recursive, extension_loaded,
-    file_get_contents, function_exists, implode, is_numeric, php_regex, preg_is_match, preg_match,
-    preg_replace, rawurldecode, stream_context_create, stripos, strpos, substr, ucfirst,
+    file_get_contents, implode, is_numeric, php_regex, preg_is_match, preg_match, preg_replace,
+    rawurldecode, stream_context_create, stripos, strpos, substr, ucfirst,
 };
 use shirabe_semver::constraint::SimpleConstraint;
 
@@ -505,8 +505,6 @@ impl HttpDownloader {
     /// @internal
     pub fn is_curl_enabled() -> bool {
         extension_loaded("curl")
-            && function_exists("curl_multi_exec")
-            && function_exists("curl_multi_init")
     }
 
     /// For testing only. Builds an HttpDownloader whose request methods are fully
diff --git a/crates/shirabe/src/util/platform.rs b/crates/shirabe/src/util/platform.rs
index ccee2953..c40f3ec5 100644
--- a/crates/shirabe/src/util/platform.rs
+++ b/crates/shirabe/src/util/platform.rs
@@ -4,8 +4,8 @@ use crate::util::ProcessExecutor;
 use crate::util::Silencer;
 use shirabe_php_shim::{
     PHP_ENV, PHP_SERVER, PhpMixed, PhpResource, PregMatches, RuntimeException, defined,
-    file_exists, file_get_contents, fstat, function_exists, getcwd, getenv, ini_get, is_readable,
-    mb_strlen, php_os_family, php_regex, posix_geteuid, posix_getpwuid, posix_getuid, posix_isatty,
+    file_exists, file_get_contents, function_exists, getcwd, getenv, ini_get, is_readable,
+    mb_strlen, php_os_family, php_regex, posix_geteuid, posix_getpwuid, posix_getuid,
     preg_is_match, preg_replace_callback, putenv, putenv_clear, realpath, stream_isatty, stripos,
     strlen, strtoupper, substr, usleep,
 };
@@ -244,9 +244,7 @@ impl Platform {
         let mut use_mb_string = USE_MB_STRING.lock().unwrap();
         if use_mb_string.is_none() {
             *use_mb_string = Some(
-                function_exists("mb_strlen")
-                    && ini_get("mbstring.func_overload")
-                        .is_some_and(|s| PhpMixed::String(s).to_bool()),
+                ini_get("mbstring.func_overload").is_some_and(|s| PhpMixed::String(s).to_bool()),
             );
         }
 
@@ -270,29 +268,7 @@ impl Platform {
             return true;
         }
 
-        // modern cross-platform function, includes the fstat
-        // fallback so if it is present we trust it
-        if function_exists("stream_isatty") {
-            return stream_isatty(fd);
-        }
-
-        // only trusting this if it is positive, otherwise prefer fstat fallback
-        if function_exists("posix_isatty") && posix_isatty(fd.clone()) {
-            return true;
-        }
-
-        let stat = Silencer::call(|| Ok(fstat(&fd)));
-        let stat = match stat {
-            Ok(s) => s,
-            Err(_) => return false,
-        };
-        let stat = match stat {
-            Some(stat) => stat,
-            None => return false,
-        };
-
-        // Check if formatted mode is S_IFCHR
-        0o020000 == (stat.mode & 0o170000)
+        stream_isatty(fd)
     }
 
     /// Whether the current command is for bash completion
diff --git a/crates/shirabe/src/util/stream_context_factory.rs b/crates/shirabe/src/util/stream_context_factory.rs
index dea964ec..bce35832 100644
--- a/crates/shirabe/src/util/stream_context_factory.rs
+++ b/crates/shirabe/src/util/stream_context_factory.rs
@@ -9,8 +9,8 @@ use crate::util::http::ProxyManager;
 use indexmap::IndexMap;
 use shirabe_ca_bundle::CaBundle;
 use shirabe_php_shim::{
-    PhpMixed, array_replace_recursive, extension_loaded, function_exists, php_uname,
-    stream_context_create, stripos, uasort,
+    PhpMixed, array_replace_recursive, extension_loaded, php_uname, stream_context_create, stripos,
+    uasort,
 };
 
 pub struct StreamContextFactory;
@@ -180,16 +180,8 @@ impl StreamContextFactory {
             let user_agent = format!(
                 "User-Agent: Composer/{} ({os}; {release}; {php_version}; {http_version}{platform}{ci})",
                 composer::get_version(),
-                os = if function_exists("php_uname") {
-                    php_uname("s")
-                } else {
-                    "Unknown".to_string()
-                },
-                release = if function_exists("php_uname") {
-                    php_uname("r")
-                } else {
-                    "Unknown".to_string()
-                },
+                os = php_uname("s"),
+                release = php_uname("r"),
                 php_version = php_version,
                 http_version = http_version,
                 platform = platform_php_version