diff --git a/base/libgit2/reference.jl b/base/libgit2/reference.jl
index 444704bef6780..47c35efe64a1b 100644
--- a/base/libgit2/reference.jl
+++ b/base/libgit2/reference.jl
@@ -73,6 +73,13 @@ function isbranch(ref::GitReference)
     return err == 1
 end
 
+function istag(ref::GitReference)
+    isempty(ref) && return false
+    err = ccall((:git_reference_is_tag, :libgit2), Cint,
+                  (Ptr{Void},), ref.ptr)
+    return err == 1
+end
+
 function isremote(ref::GitReference)
     isempty(ref) && return false
     err = ccall((:git_reference_is_remote, :libgit2), Cint,
@@ -96,6 +103,15 @@ function peel{T <: GitObject}(::Type{T}, ref::GitReference)
     return T(obj_ptr_ptr[])
 end
 
+function ref_list(repo::GitRepo)
+    with(StrArrayStruct()) do sa
+        sa_ref = Ref(sa)
+        @check ccall((:git_reference_list, :libgit2), Cint,
+                      (Ptr{StrArrayStruct}, Ptr{Void}), sa_ref, repo.ptr)
+        convert(Vector{AbstractString}, sa_ref[])
+    end
+end
+
 function create_branch(repo::GitRepo,
                        bname::AbstractString,
                        commit_obj::GitCommit;
diff --git a/base/libgit2/tag.jl b/base/libgit2/tag.jl
index 83b822ea85a2f..71f40b3a494c5 100644
--- a/base/libgit2/tag.jl
+++ b/base/libgit2/tag.jl
@@ -31,10 +31,13 @@ function tag_create(repo::GitRepo, tag::AbstractString, commit::Union{AbstractSt
 end
 
 function name(tag::GitTag)
-    return String(ccall((:git_tag_name, :libgit2), Cstring, (Ptr{Void}, ), tag.ptr))
+    str_ptr = ccall((:git_tag_name, :libgit2), Cstring, (Ptr{Void}, ), tag.ptr)
+    str_ptr == C_NULL && throw(Error.GitError(Error.ERROR))
+    return String(str_ptr)
 end
 
 function target(tag::GitTag)
-    oid_ptr = Ref(ccall((:git_tag_target_id, :libgit2), Ptr{Oid}, (Ptr{Void}, ), tag.ptr))
-    return oid_ptr[]
+    oid_ptr = ccall((:git_tag_target_id, :libgit2), Ptr{Oid}, (Ptr{Void}, ), tag.ptr)
+    oid_ptr == C_NULL && throw(Error.GitError(Error.ERROR))
+    return Oid(oid_ptr)
 end
diff --git a/test/libgit2.jl b/test/libgit2.jl
index d36ede39426fd..a446d592fc7c7 100644
--- a/test/libgit2.jl
+++ b/test/libgit2.jl
@@ -219,6 +219,13 @@ mktempdir() do dir
                 @test LibGit2.iszero(commit_oid2)
                 commit_oid2 = LibGit2.commit(repo, commit_msg2; author=test_sig, committer=test_sig)
                 @test !LibGit2.iszero(commit_oid2)
+                auths = LibGit2.authors(repo)
+                @test length(auths) == 3
+                for auth in auths
+                    @test auth.name == test_sig.name
+                    @test auth.time == test_sig.time
+                    @test auth.email == test_sig.email
+                end
 
                 # lookup commits
                 cmt = LibGit2.get(LibGit2.GitCommit, repo, commit_oid1)
@@ -315,6 +322,11 @@ mktempdir() do dir
                 tags = LibGit2.tag_list(repo)
                 @test length(tags) == 1
                 @test tag1 in tags
+                tag1ref = LibGit2.GitReference(repo, "refs/tags/$tag1")
+                @test isempty(LibGit2.fullname(tag1ref)) #because this is a reference to an OID
+                tag1tag = LibGit2.peel(LibGit2.GitTag,tag1ref)
+                @test LibGit2.name(tag1tag) == tag1
+                @test LibGit2.target(tag1tag) == commit_oid1
 
                 tag_oid2 = LibGit2.tag_create(repo, tag2, commit_oid2)
                 @test !LibGit2.iszero(tag_oid2)
@@ -322,6 +334,9 @@ mktempdir() do dir
                 @test length(tags) == 2
                 @test tag2 in tags
 
+                refs = LibGit2.ref_list(repo)
+                @test refs == ["refs/heads/master","refs/heads/test_branch","refs/tags/tag1","refs/tags/tag2"]
+
                 LibGit2.tag_delete(repo, tag1)
                 tags = LibGit2.tag_list(repo)
                 @test length(tags) == 1